KR20110124698A - Electrode for fuel cell, preparing method thereof, and membrane electrode assembly and fuel cell employing the same - Google Patents

Abstract

PURPOSE: An electrodefor a fuel cell is provided to stably maintain properties from the early stage of operation in a high temperature operation condtion. CONSTITUTION: An electrode(1) for a fuel cell comprising an electrode catalyst layer(5), wherein the electrode catalyst layer comprises an electrode catalyst including a conductive carrier(11) and catalyst particles(13) supported on the conductive carrier, and the electrode catalyst includes an acid impregnated electrode catalyst(20) in which the conductive carrier is impregnated with an acid component having proton conductivity and a non-impregnated electrode catalyst(10) in which the conductive carrier is not impregnated with the acid component.

Description

Electrode for fuel cell, method for manufacturing same, and membrane electrode assembly and fuel cell having same {Electrode for fuel cell, preparing method etc, and membrane electrode assembly and fuel cell employing the same}

The present invention relates to a fuel cell electrode, a fuel cell electrode manufacturing method, a membrane electrode assembly provided with the fuel cell electrode, and a fuel cell.

Currently, a fuel cell using a fluorine-based electrolyte membrane represented by a perfluorosulfonic acid membrane such as Nafion (trademark, manufactured by DuPont) is used as an electrolyte membrane for a fuel cell. In the case of this electrolyte membrane, the hydrophobic main chain and the hydrophilic side chain are phase separated to form a so-called ion cluster structure. As a proton transport mode, it is known that many water molecules are taken in this electrolyte membrane structure to promote dissociation of sulfonic acid groups and at the same time to express high proton conductivity by utilizing high motility of water molecules.

However, the fuel cell as described above is not limited to the operating temperature of 70 to 80 ° C due to the proton conduction depending on the water, but also requires a humidifier as an auxiliary device, which complicates the water management system. In addition, from the viewpoint of a fuel cell system, the operating temperature is a big limitation, and in addition to the problem of poisoning of the catalyst with carbon monoxide, which is a by-product generated when hydrogen gas is produced, a carbon monoxide removing device is also indispensable. There has been a problem that the fuel cell system as a whole becomes very expensive.

In view of these problems, in the field of fuel cells, which are attracting attention as the next-generation clean energy, development of an electrolyte membrane capable of conducting protons under no-humidity or low-humidity to enable operation at a high temperature of 100 ° C. or higher is actively carried out. It is done. In this way, if an electrolyte membrane capable of proton conduction at a high temperature that does not depend on water is provided, the fuel cell system can be simplified, and it can be expected to be used as a home cogeneration or an automobile. One such fuel cell is, for example, a phosphoric acid fuel cell (PAFC), and various developments have been made in the past (for example, refer to Patent Documents 1 and 2 below).

In recent years, various proposals have been made regarding a polymer electrolyte fuel cell (PEFC) which operates at 100 ° C or higher. In general, in the power generation above 100 ° C, the catalytic activity is improved, suggesting that the degree of poisoning by carbon monoxide may be reduced, and furthermore, it is considered that fuel cell life is improved. However, since the water molecules cannot be stably present in the operation in the medium temperature range of about 150 ° C, for example, it depends on the water medium mainly based on polybenzimidazole impregnated with phosphoric acid, as in Patent Document 3 below. A fuel cell using an electrolyte system which is not used has been proposed. In such a fuel cell, it is considered that power generation is possible even in a medium temperature region of about 150 ° C.

[Patent Document 1]

Japanese Patent Laid-Open No. 10-144324

[Patent Document 2]

Japanese Patent Laid-Open No. 2001-52718

[Patent Document 3]

US Patent No. 5,525,436.

Since a fuel cell using a polybenzimidazole-based electrolyte impregnated with phosphoric acid uses phosphoric acid as a proton conductor, phosphoric acid must act as a proton conductor both in the electrolyte and in the electrode catalyst layer in order to improve power generation characteristics. . For this reason, there existed a problem which the degree of dispersion of phosphoric acid and the amount of phosphoric acid in an electrode catalyst layer determine power generation performance.

In addition, in a fuel cell using an electrolyte membrane impregnated with phosphoric acid, when power is generated for a long time, phosphoric acid leaches out of the electrolyte membrane and flows out to the outside, which makes it difficult to exert sufficient power generation performance for a long time. In addition, phosphoric acid leaching in the electrolyte membrane during the phosphoric acid outflow process prevents the voids for gas diffusion in the electrode catalyst layer, thereby causing insufficient electrode reaction.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel cell electrode, a method for manufacturing a fuel cell electrode, and a fuel cell capable of stably maintaining characteristics from an initial stage under high temperature operating conditions. It is done.

In order to solve the said subject, according to one aspect of the present invention,

An electrode for a fuel cell comprising an electrode catalyst layer,

The electrode catalyst layer comprises an electrode catalyst comprising a conductive carrier and catalyst particles supported on the conductive carrier,

The electrode catalyst is provided with an electrode for a fuel cell comprising an acid impregnated electrode catalyst in which an acid component having proton conductivity is impregnated in the conductive carrier and an acid impregnated electrode catalyst in which the acid component is not impregnated in the conductive carrier.

When the electrode catalyst layer is formed, the mixing ratio of the weight of the acid-impregnated electrode catalyst to the weight of the acid-impregnated electrode catalyst may be 5 to 95: 95 to 5. When the electrode catalyst layer is composed of an acid-impregnated electrode catalyst and an acid-impregnated electrode catalyst composed of such a ratio, the water-soluble free acid leached from the polymer electrolyte membrane can be adsorbed appropriately. As a result, the phenomenon that the space | gap of a gas diffusion path can be clogged can be suppressed, and durability of an electrode catalyst layer can be improved.

The conductive carrier may be a carbon material.

The catalyst particles are platinum (Pt), gold (Au), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru), cobalt (Co), iron (Fe), lead (Pb), manganese It may include at least one metal selected from the group consisting of (Mn), chromium (Cr), gallium (Ga), tin (Sn), molybdenum (Mo), and vanadium (V). Specifically, the catalyst particles are platinum (Pt) alone; Platinum, gold (Au), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru), cobalt (Co), iron (Fe), lead (Pb), manganese (Mn), chromium ( Mixtures or alloys comprising at least one metal selected from the group consisting of Cr), gallium (Ga), tin (Sn), molybdenum (Mo), and vanadium (V); Or gold (Au), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru), cobalt (Co), iron (Fe), lead (Pb), manganese (Mn), chromium (Cr) , Gallium (Ga), tin (Sn), molybdenum (Mo) and vanadium (V) may be a mixture or alloy of two or more metals selected from the group consisting of.

The acid may be at least one acid selected from the group consisting of phosphoric acid, phosphoric acid derivatives, phosphonic acid, phosphonic acid derivatives, phosphinic acid, phosphinic acid derivatives, sulfuric acid, sulfuric acid derivatives, sulfonic acid and sulfonic acid derivatives.

The electrode catalyst layer is polytetrafluoroethylene (PTFE), poly (vinylidene fluoride) (PVDF), tetrafluoroethylene-hexafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polychloro Trifluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (ETFE), styrene butadiene rubber (SBR), may further comprise at least one hydrophobic binder resin selected from the group consisting of polyurethane.

The conductive carrier may be porous particles having a BET specific surface area of 50 to 1500 m ² / g.

By using such a conductive carrier, a catalyst particle, an acid component, and a hydrophobic binder resin, the characteristics of the fuel cell electrode according to one aspect of the present invention can be improved, and further, a fuel having the fuel cell electrode according to one aspect of the present invention. The power generation characteristics of the battery can be improved.

In order to solve the said subject, according to another viewpoint of this invention,

An application step of applying a composition for an electrode catalyst layer comprising an acid impregnated electrode catalyst having an acid component having proton conductivity impregnated in a conductive carrier and an acid impregnated electrode catalyst having the acid component not impregnated in the conductive carrier; And

Provided is a method of manufacturing an electrode for a fuel cell having a drying step of drying the coated composition for a catalyst layer to form an electrode catalyst layer.

The mixing ratio of the weight of the acid-impregnated electrocatalyst in the catalyst layer composition: the weight of the acid-impregnated electrocatalyst may be 5 to 95: 95 to 5.

The acid-impregnated electrode catalyst may be prepared by a method including dispersing the acid-impregnated electrode catalyst in the acid component to perform vacuum heat treatment. For example, the acid-impregnated electrode catalyst disperses the acid-impregnated electrode catalyst in the acid component, and then maintains the dispersion under reduced pressure to impregnate the acid component in the pores of the conductive carrier of the acid-impregnated electrode catalyst. Obtaining an acid impregnated electrode catalyst;

Heat-treating the acid impregnated electrode catalyst to impregnate the acid component with higher concentration in pores of the acid impregnated electrode catalyst; And

It may be prepared by a method comprising the step of washing and drying the acid-impregnated electrocatalyst.

The heat treatment may be carried out at 100 ~ 150 ℃. By heat treatment under a reduced pressure lower than atmospheric pressure in this temperature range, the acid can be efficiently impregnated into the pores of the conductive carrier without denaturing the acid. It is preferable that the said acid is an aqueous solution of 85 weight% or less of concentration. By using the acid aqueous solution of such a concentration, an acid aqueous solution has the viscosity suitable for a process, and can carry out an acid impregnation process efficiently.

In order to solve the said subject, according to another viewpoint of this invention,

A fuel cell membrane electrode assembly (MEA) comprising a cathode and an anode positioned opposite to each other, and a solid electrolyte membrane positioned between the cathode and the anode,

There is provided a membrane electrode assembly in which the solid electrolyte membrane comprises a basic polymer doped with an acid component, wherein at least one of the cathode electrode and the anode electrode is an electrode for a fuel cell according to one aspect of the present invention described above.

In order to solve the said subject, according to another viewpoint of this invention,

A fuel cell including a membrane electrode assembly including a fuel cell electrode according to an aspect of the present invention is provided. For example, the fuel cell may be a polymer electrolyte fuel cell in which a fuel gas is supplied to an anode electrode and an oxidant gas is supplied to the cathode electrode, and an operating temperature is 100 ° C. or higher.

According to this structure, since acid components such as phosphoric acid, which is a proton pass, are effectively impregnated into the pores of the conductive carrier of the acid impregnated electrode catalyst, it is necessary to improve the power generation characteristics of the fuel cell and to activate the initial generation by increasing the catalytic reaction area. The aging (conditioning) time can be shortened. In addition, since the acid-impregnated electrode catalyst and the acid-impregnated electrode catalyst have an electrode catalyst layer uniformly dispersed, the acid leached from the inside of the polymer electrolyte membrane can be trapped over time, and the gas diffusion in the electrode catalyst layer It is possible to maintain voids for the purpose. As a result, the fall of the power generation characteristic of a fuel cell can be reduced, and durability can be improved.

As described above, according to the fuel cell electrode of the present invention, the membrane electrode assembly and the fuel cell employing the same, the operation is carried out by using a catalyst which is treated by adsorbing acid to catalyst particles in advance to uniformly arrange the acid in forming the electrode catalyst layer. The characteristics can be stably maintained from the beginning.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the structure of the electrode for fuel cells which concerns on one Embodiment of this invention.
2 is a cross-sectional view showing the structure of a membrane electrode assembly including a fuel cell electrode according to an embodiment of the present invention.
3 is a graph showing power generation characteristics of a single cell according to the Examples and Comparative Examples of the present invention.
4 is a graph showing changes over time of power generation characteristics of a single cell according to Examples and Comparative Examples of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of this invention is described in detail with reference to an accompanying drawing. In addition, in this specification and drawing, the component which has substantially the same functional structure is abbreviate | omitted redundant description by using the same code | symbol.

Fuel Cell Electrode

First, with reference to FIG. 1, the structure of the electrode for fuel cells which concerns on 1st Embodiment of this invention is demonstrated. 1 is an explanatory diagram showing a structure of an electrode for a fuel cell according to the present embodiment.

The fuel cell electrode 1 according to the present embodiment has a polymer electrolyte membrane 3 and an electrode catalyst layer 5 as illustrated in FIG. 1.

Polymer Electrolyte Membrane (3)

First, the polymer electrolyte membrane 3 according to the present embodiment will be described. The polymer electrolyte membrane 3 includes a basic polymer doped with an acid component and supports the electrode catalyst layer 5 described later.

Although a basic polymer is not specifically limited, In consideration of compatibility with the acid and polar solvent doped with this basic polymer, film forming processability, heat resistance, etc., it is preferable that a main skeleton is an aromatic engineering plastic. Such an aromatic engineering plastic is not particularly limited as long as it is an engineering plastic having aromaticity. For example, polybenzimidazole, poly (pyridine), poly (pyrimidine), polyimidazole, polybenzothiazole, polybenzooxa Sol, polyoxazole, polyquinoline, polyquinoxaline, polythiadiazole, poly (tetradipyrene), polyoxazole, polythiazole, polyvinylpyridine, polyvinylimidazole, polyetheretherketone, poly Phenylene oxide, aromatic polyimide, aromatic polyamide, polycarbonate, polyethylene terephthalate, polyarylate, polyimide, etc. are mentioned.

The polymer electrolyte membrane 3 is doped with an acid component, for example, a water-soluble free acid. The water-soluble free acid according to the present embodiment is not particularly limited, and various acids such as phosphoric acid, phosphonic acid, phosphinic acid, sulfuric acid, methylsulfonic acid, trifluoromethyl sulfonic acid and trifluoromethane sulfonylamide sulfonic acid may be mentioned. Can be. Among the acids described above, the water-soluble free acid according to the present embodiment is preferably an acidic inorganic phosphorus compound or an acidic organic phosphorus compound from the viewpoint of thermal stability.

As said acidic inorganic phosphorus compound, phosphoric acid, polyphosphoric acid, condensed phosphoric acid, phosphonic acid, phosphinic acid, etc. are mentioned, for example. As said acidic organic phosphorus compound, For example, alkyl phosphate represented by methyl phosphate, ethyl phosphate, etc., alkyl phosphonic acid represented by vinyl phosphonic acid, allyl phosphonic acid, methyl phosphonic acid, ethyl phosphonic acid, etc., And acidic phosphoric acid esters such as aryl phosphonic acid such as phenyl phosphonic acid, methyl phosphate ester, ethyl phosphate ester, butyl phosphate ester and the like.

As the water-soluble free acid, a mixture of free acid and Lewis base or a mixture of free acid and organic salt may be used.

As a Lewis base which can be used in admixture with the free acid, for example, an azole compound such as imidazole, triazole, benzimidazole, benzotriazole, nitrogen-containing complexes such as pyridine, pyridazine, pyrimidine, pyrazine, and triazine And nitrogen-containing condensed polycyclic heterocyclic compounds such as six-membered ring compounds, quinoline, quinoxaline, indole, and phenazine, and nucleic acid bases such as purine, uracil, thymine, cytosine, adenine, and guanine.

Moreover, as an organic salt which can be used by mixing with a free acid, the neutral salt which consists of an organic compound cation and an oxo acid anion is mentioned, for example. As an organic compound cation, the cations of a heterocyclic compound, especially the cations of the 3-6 membered heterocyclic compound containing 1-5 heteroatoms, 3 containing 1-5 nitrogen atoms as a hetero atom in particular Cations of the 6-membered ring compound, and the like, and specific examples thereof include imidazolium cation, pyrrolidinium cation, piperidinium cation, and pyridinium cation. Moreover, a linear quaternary ammonium cation, quaternary phosphonium cation, etc. can also be used.

The polymer electrolyte membrane 3 including the polymer electrolyte and the water-soluble free acid as described above may be manufactured by a known method. The manufacturing method of the polymer electrolyte membrane is briefly described as follows. First, the polymer electrolyte solution is adjusted using a known solvent, and the adjusted solution is cast-coated on a substrate using a known coating method and dried. Thereafter, the polymer electrolyte membrane 3 according to the present embodiment can be produced by immersing the film-formed polymer electrolyte membrane in a solution containing a water-soluble free acid to obtain a water-soluble free acid-doped membrane swollen with a water-soluble free acid. .

In addition to the above method, for example, a polymer electrolyte membrane can be produced by the following method. That is, a solution containing a polymer electrolyte and a water-soluble free acid is adjusted using a known solvent, and the adjusted solution is cast on a substrate using a known coating method. Thereafter, the polymer electrolyte membrane 3 according to the present embodiment can be produced by drying the polymer electrolyte membrane cast on the substrate.

The doping amount of the water-soluble free acid to the polymer electrolyte may be appropriately set in accordance with the performance required for the polymer electrolyte membrane.

Electrocatalyst layer (5)

Next, the electrode catalyst layer 5 which concerns on this embodiment is demonstrated in detail.

The electrode catalyst layer 5 according to the present embodiment is a layer supported by the polymer electrolyte membrane 3 as shown in FIG. 1. In this electrode catalyst layer 5, an acid impregnated electrode catalyst subjected to pretreatment with an acid described later and an acid impregnated electrode catalyst not pretreated are uniformly dispersed. The difference between an acid-impregnated electrode catalyst (hereinafter also referred to as a doping catalyst) and an acid-impregnated electrode catalyst (hereinafter also referred to as an undoped catalyst) included in the electrode catalyst layer 5 according to the present embodiment is the presence or absence of pretreatment with an acid described later. to be.

The electrode catalyst according to the present embodiment consists of a conductive carrier and catalyst particles supported on the conductive carrier. Such an electrode catalyst is the undoped catalyst 10 which concerns on this embodiment. The undoped catalyst 10 is subjected to pretreatment with an acid described below to form the dope catalyst 20.

That is, the undoped catalyst 10 is composed of the conductive carrier 11 and the electrode catalyst 13 supported on the conductive carrier 11, as shown in the lower left of FIG. 1, the doping catalyst 20 is shown in FIG. As shown in the lower right of the figure, the conductive carrier 15 impregnated with acid by the pretreatment and the catalyst particles 13 supported by the conductive carrier 15 subjected to the pretreatment are formed.

The conductive carrier according to the present embodiment is not particularly limited as long as it has conductivity. For example, a porous body mainly composed of a carbon material having conductivity can be used. As an example of such a carbon material, carbon black, such as furnace black, Ketjen black, acetylene black, activated carbon, graphite, etc. are mentioned, for example.

Here, the specific surface area of the conductive carrier may be appropriately selected in accordance with the properties of the polymer electrolyte membrane 3 according to the present embodiment. For example, when the content of the water-soluble free acid contained in the polymer electrolyte membrane 3 is relatively low (hereinafter also referred to as a low doping state), the specific surface area of the conductive carrier may be small. In addition, when the content of the water-soluble free acid contained in the polymer electrolyte membrane 3 is relatively high (hereinafter also referred to as a high doping state), in order to trap the acid leached from the polymer electrolyte membrane in the high doping state over time. It is preferable that the specific surface area of a conductive support is large. In addition, from the viewpoint of oxidation resistance of carbon, which is a conductive carrier, it is preferable to use graphitized carbon blacks rather than general carbon blacks as carriers for catalysts in solid polymer fuel cells operating at high temperatures.

Although one BET specific surface area is one of such specific surface areas, it is preferable that the BET specific surface area of the electroconductive carrier which concerns on this embodiment is 50-1,500 m <^2> / g, for example. This BET specific surface area can be measured using a known method such as adsorption method which measures the adsorption occupied area on the surface of powder particles at low temperature and measures it from the adsorption amount, or wet heat method, permeation method and diffusion rate method. Can be. Carbon carriers with too much graphite structure are not preferable because their specific surface area is small, so that the water repellency increases, so that the acid component is hardly absorbed and the absorption of the acid component takes time.

The catalyst particles supported on the conductive carrier are not particularly limited, but for example, platinum or an alloy containing platinum and having at least one non-noble metal can be used. Examples of alloys containing platinum and having at least one non-noble metal include Pt-Co alloys containing platinum and cobalt, Pt-Ru alloys containing platinum and ruthenium, Pt-Fe alloys containing platinum and iron, and the like. Can be.

In addition to alloys containing platinum or platinum and having at least one non-noble metal, gold, lead, iron, manganese, cobalt, chromium, gallium, vanadium, tungsten, ruthenium, iridium, palladium, rhodium, or any two thereof The above alloys are mentioned.

Here, the supporting amount of the catalyst particles supported on the conductive carrier according to the present embodiment can be appropriately determined according to the performance required for the fuel cell electrode according to the present embodiment, and the method for supporting the catalyst particles on the conductive carrier is also a known method. What is necessary is just to use suitably.

In the present embodiment, the acid is added to the conductive carrier of the undoped catalyst 10 by performing pretreatment with acid (for example, vacuum heat treatment using acid) to the electrode catalyst composed of the conductive carrier and the catalyst particles as described above. Impregnate As a result, the undoped catalyst subjected to the pretreatment becomes a doping catalyst.

Acids used in vacuum heat treatment are phosphoric acid and derivatives thereof, phosphonic acid and derivatives thereof, phosphinic acid and derivatives thereof, sulfuric acid and derivatives thereof, sulfonic acid and derivatives thereof such as and methyl sulfonic acid, trifluoromethyl sulfonic acid, tri Various acids such as fluoromethanesulfonylamide sulfonic acid. In the vacuum heat treatment according to the present embodiment, one kind or a combination of two or more kinds of these acids can be used. Among the acids mentioned above, it is particularly preferable that they are acidic inorganic phosphorus compounds or acidic organic phosphorus compounds from the viewpoint of thermal stability and the like.

As an acidic inorganic phosphorus compound, phosphoric acid (orthophosphoric acid), polyphosphoric acid, condensed phosphoric acid, phosphonic acid, phosphinic acid, etc. are mentioned, for example. As the acidic organic phosphorus compound, for example, alkyl phosphoric acid represented by methyl phosphoric acid or ethyl phosphoric acid or the like, vinyl phosphonic acid, allyl phosphonic acid, alkyl phosphonic acid or ethyl phosphonic acid or the like And acidic phosphoric acid esters such as aryl phosphonic acid such as phosphonic acid, methyl phosphate ester, ethyl phosphate ester, butyl phosphate ester and the like. Among these phosphorus compounds, in particular, at least one acid selected from the group consisting of orthophosphoric acid, condensed phosphoric acid, alkyl phosphoric acid, phosphonic acid. The alkyl phosphoric acid may specifically be C1 to C20 alkyl phosphoric acid, and the alkyl phosphonic acid may specifically be C1 to C20 alkyl phosphonic acid.

In the vacuum heat treatment using an acid, first, the electrode catalyst (the undoped catalyst 10) is dispersed in a solution (for example, an aqueous solution) containing the above-described acid, and after stirring, it is maintained for a predetermined time in a vacuum apparatus. As a result, the air present in the pores of the conductive carrier is released and acid is impregnated into the pores instead. Thereafter, the electrode catalyst impregnated with acid is subjected to a heat treatment, for example, in a range of 100 to 150 ° C. The electrode catalyst after the heat treatment is filtered after washing with water, and the doped catalyst 20 according to the present embodiment can be produced. By heat-processing at the temperature of 100 degreeC or more, the water molecule in the phosphoric acid solution which permeated in the pore comes out, and it becomes possible to make acid enter in after it falls out. As a result, an acid as described above is impregnated with high density inside the pores of the conductive carrier.

Moreover, when the heat processing temperature is less than 100 degreeC, since it is difficult to remove the water molecule in the solution containing an acid, it is not preferable. Moreover, when the heat processing temperature is more than 150 degreeC, since the property of the impregnated acid (for example, phosphoric acid etc.) starts to denature, it is unpreferable.

In addition, the concentration of the acid solution (eg, phosphoric acid aqueous solution) used in the vacuum heat treatment may be 85% by weight or less. By setting it as the solution of such a density | concentration, an acid solution turns into a solution of relatively low viscosity suitable for vacuum heat processing, and can impregnate an acid efficiently.

Here, the amount of acid (ie, doping amount) impregnated in the undoped catalyst 10 can be appropriately determined so that the performance required for the fuel cell electrode according to the present embodiment can be exhibited. In addition, the doping amount can be controlled by appropriately adjusting the concentration of the acid solution used for vacuum pretreatment, the solution amount, the catalyst species (specific surface area of the conductive carrier), the heat treatment temperature, the treatment time, and the like. In addition, the doping amount may be measured using various analytical methods, but may be quantified using, for example, inductively coupled plasma-atomic emission spectrometry (ICP-AES).

In this embodiment, the electrode catalyst layer 5 is manufactured by combining and using the dope catalyst 20 produced in this way and the undoped catalyst 10 which is not subjected to the vacuum heat treatment by an acid. At this time, the respective catalysts are mixed such that the weight ratio of the doped catalyst 20 to the undoped catalyst 10 is 5 to 95:95 to 5, and the electrode catalyst layer 5 is formed to uniformly disperse each catalyst. Specifically, the ratio of the dope catalyst 20 and the undoped catalyst 10 may be a weight ratio of the dope catalyst 20 to the undoped catalyst 10 may be 80 to 95: 5 to 20.

By forming the electrode catalyst layer 5 so that the initial mixing ratio of the dope catalyst and the undoped catalyst is in the above-mentioned range, the acid distribution which is the proton pass (proton conduction path) in the electrode catalyst layer 5 can be made uniform, and further, The characteristic of the fuel cell using such an electrode can be improved. In addition, in order to stabilize the acid distribution in the electrode catalyst layer 5, the initial operation conditioning (aging) time can be shortened. In addition, since the undoped catalyst having room for impregnating the acid (water-soluble free acid) leached from the polymer electrolyte membrane 3 into the pores of the conductive carrier is present in the electrode catalyst layer 5, durability of the electrode can be improved. In addition, an acid leached from the polymer electrolyte membrane 3 can be trapped to ensure a gas diffusion gap. As a result, the fuel cell electrode having such an electrode catalyst layer 5 can improve the characteristics and durability of the fuel cell.

When the weight ratio of the dope catalyst 20 is less than 5 (that is, the content ratio of the undoped catalyst is greater than 95) and when the weight ratio of the dope catalyst 20 is greater than 95 (that is, the weight ratio of the undoped catalyst is less than 5). ), The same effects as described above can be obtained, but the effects are not satisfactory. When the weight ratio of the doping catalyst 20 is 80 to 95 and the weight ratio of the undoped catalyst 10 is 5 to 20, the characteristics and durability of the fuel cell as described above can be further improved.

In the present embodiment, the electrode catalyst layer 5 is formed on the polymer electrolyte membrane 3 by solid-forming the electrode catalyst mixed in the same ratio as described above with a binder. The content of the binder may be 50 to 500% by weight, for example 10 to 250% by weight, specifically 20 to 200% by weight, based on the total weight of the undoped catalyst 10 and the doped catalyst 20. have. Within the above binder content range, it is possible to balance the mechanical and output characteristics of the electrode catalyst layer.

As a binder used for formation of the electrode catalyst layer 5, for example, a fluororesin excellent in heat resistance can be used. In the case of using a fluororesin as a binder, a fluororesin having a melting point of 400 ° C. or less is preferable, and as such a fluororesin, polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkylvinyl ether copolymer, polyvinylidene fluoride, tetra Resin excellent in hydrophobicity and heat resistance, such as a fluoroethylene-hexafluoroethylene copolymer and perfluoroethylene, can be used. By adding a hydrophobic binder, the catalyst layer can be prevented from being excessively wetted by water generated with the power generation reaction, thereby preventing the diffusion of fuel gas and oxygen inside the fuel electrode and the oxygen electrode.

A conductive agent may also be added to the electrode catalyst layer 5 according to the present embodiment. As the conductive agent, any material can be used as long as it is an electrically conductive material, and various metals or carbon materials may be used. As an example of such a carbon material, carbon black, such as acetylene black, activated carbon, graphite, etc. are mentioned, These carbon materials and various metals can be used individually or in mixture.

In the above, the electrode catalyst layer 5 which concerns on this embodiment was demonstrated, referring FIG. FIG. 1 schematically shows a part of the electrode catalyst layer 5, and it should be noted that the undoped catalyst 10 and the doped catalyst 20 are uniformly dispersed throughout the electrode catalyst layer 5.

Method for producing electrode catalyst layer

Next, the manufacturing method of the electrode catalyst layer which concerns on this embodiment is demonstrated in order.

The method for producing an electrode catalyst layer according to the present embodiment includes (1) a step of producing an undoped catalyst, (2) a vacuum heat treatment step of using an acid (a step of producing a doping catalyst), (3) a film forming step, and (4) a drying step. It includes four processes of.

(1) manufacturing process of undoped catalyst

This step is a step of preparing an undoped catalyst by supporting catalyst particles on a conductive carrier using the above-described conductive carrier and catalyst particles. Since the well-known method can be used for the method of supporting the catalyst particle which concerns on this embodiment on a conductive support, detailed description is abbreviate | omitted here.

(2) vacuum heat treatment step with acid

This step is a step of manufacturing a doping catalyst by impregnating the above-described acid component (for example, phosphoric acid, etc.) on the conductive carrier of the undoped catalyst using the undoped catalyst prepared in step (1). In addition, below, the case where phosphoric acid is impregnated in the pore of a catalyst carrier is demonstrated as an example.

First, a predetermined amount of the undoped catalyst prepared in step (1) is weighed, dispersed in an aqueous solution of phosphoric acid having a concentration of 85% by weight or less, and stirred using a mechanical stirrer, a magnetic stirrer, or the like. Of course, the mechanism used for stirring is not limited to a mechanical stirrer or a magnetic stirrer, If the undoped catalyst can fully be mixed in aqueous solution of phosphoric acid, another mechanism can be used. In addition, when bubbles are generated by stirring, the solution in stirring can be degassed by vacuum defoaming or centrifugal defoaming.

After the agitation treatment as described above, the obtained slurry is placed in a vacuum apparatus and held for a predetermined time (for example, about 1 hour) to impregnate phosphoric acid in the pores of the conductive carrier. Thereafter, the electrode catalyst impregnated with phosphoric acid is subjected to heat treatment in the range of 100 to 150 ° C. As a result, water molecules present in the pores of the conductive carrier are removed, and phosphoric acid is impregnated into the pores at high density. Subsequently, the electrode catalyst impregnated with phosphoric acid is washed with water and then dried to obtain an electrode catalyst impregnated with phosphoric acid (ie, a doping catalyst).

(3) Filmmaking Process

First, the dope catalyst prepared by the step (2) and the undoped catalyst prepared by the step (1) are mixed to a predetermined weight ratio. That is, the two types of electrode catalysts described above are mixed so that the weight ratio of the dope catalyst 20 to the undoped catalyst 10 is 5 to 95:95 to 5, for example, 80 to 95: 5 to 20.

Next, the mixture of the obtained electrode catalysts is dispersed in a binder in a solution state and stirred to prepare a paste-formed electrode catalyst. The solvent used for dissolving the binder is preferably determined in consideration of the compatibility of the electrode catalyst and the binder composition.

Subsequently, the electrode catalyst layer is formed by casting the paste electrode catalyst onto an electrode support base material using a known coating method. As a coating method, the method of casting to a base material using a die coater, a coma coater (trademark), a doctor blade, an application roll, etc. is mentioned, for example.

(4) drying process

The drying step is a step of drying the electrode catalyst layer formed by the film forming step 3 at least 20 minutes or more at the boiling point of the solvent, preferably 150 ° C. or less. This drying process aims at removing water and a solvent contained in the electrode catalyst layer. By drying for a predetermined time in the above-described temperature range, the moisture and the solvent contained in the electrode catalyst layer may be volatilized to sufficiently dry the electrode catalyst layer. By passing through such a drying process, the electrode catalyst layer which concerns on this embodiment can be obtained.

Moreover, you may perform the preliminary drying process for the purpose of roughly removing the solvent contained in an electrode catalyst layer at the same time as forming the surface of an electrode catalyst layer prior to the said drying process.

Membrane electrode assembly

In the fuel cell according to the present embodiment, a plurality of single cells are sandwiched in a pair of holders. However, the cell includes a membrane electrode assembly (MEA) and a bipolar plate disposed on both sides in the thickness direction of the membrane electrode assembly, and the operating temperature is 100 to 200 ° C., the humidity is not humidified or the relative humidity is 50% or less. It will work in the condition. The bipolar plate is made of a conductive metal, carbon, or the like, and is bonded to the membrane electrode assembly to function as a current collector and to supply oxygen and fuel to the electrode catalyst layer of the membrane electrode assembly.

First, the membrane electrode assembly according to the present embodiment will be described with reference to FIG. 2. 2 is a cross-sectional view showing the structure of the membrane electrode assembly according to the present embodiment.

As shown in FIG. 2, the membrane electrode assembly 100 according to the present embodiment includes the electrode catalyst layers 5 and 5 ′ and the electrode catalyst layers disposed on both sides of the polymer electrolyte membrane 3 and the polymer electrolyte membrane 3 in the thickness direction. 5 and 5 ', respectively, and the first gas diffusion layers 30 and 30' and the second gas diffusion layers 40 and 40 'respectively stacked on the first gas diffusion layers 30 and 30'. A pair of electrodes is comprised by the electrode catalyst layers 5 and 5 ', the 1st gas diffusion layers 30 and 30', and the 2nd gas diffusion layers 40 and 40 '.

Here, since the polymer electrolyte membrane 3 and the electrode catalyst layers 5 and 5 'are the same as described above, the description thereof will not be repeated here.

The first gas diffusion layers 30 and 30 'and the second gas diffusion layers 40 and 40' are each formed of a carbon sheet or the like, and the oxygen gas and the fuel gas supplied through the bipolar plate are transferred to the electrode catalyst layers 5 and 5 '. ) To the front of the spread.

The fuel cell including the membrane electrode assembly 100 operates at a temperature of 100 to 200 ° C., for example, hydrogen gas is supplied as a fuel gas through a bipolar plate to one electrode catalyst layer side, and the other electrode catalyst layer. On the side, for example, oxygen gas is supplied as an oxidant through a bipolar plate. Hydrogen is oxidized in one electrode catalyst layer to produce protons, which protons conduct the polymer electrolyte membrane 3 to reach the other electrode catalyst layer, and protons and oxygen electrochemically in the other electrode catalyst layer. React to produce water and at the same time generate electrical energy.

In addition, hydrogen supplied as a fuel may be hydrogen generated by the reforming of a hydrocarbon or alcohol, and oxygen supplied as an oxidant may be supplied in a state contained in air.

Fuel cell

The following describes the fuel cell according to the present embodiment.

According to the present embodiment, a polymer electrolyte fuel cell includes a laminate in which a plurality of membrane electrode assemblies and a bipolar plate are alternately stacked, an anode collector, an anode collector, and an insulator provided on both sides of the laminate. An end plate and a end plate are respectively attached to the current collector for molten metal and the current collector for cathode.

On the anode side of each bipolar plate, a fuel flow path through which fuel flows is installed, and on the cathode side of each bipolar plate, an oxidant flow path through which an oxidant flows is installed. In addition, instead of the bipolar plate, a fuel plate provided with a fuel flow path, an oxidizer plate installed with an oxidizer flow path, and a separator interposed between the fuel plate and the oxidizer plate may be installed.

Each cell serving as the center of each membrane electrode assembly functions as a unit cell of a fuel cell, and the power generated from each cell is output to the outside via an anode current collector and a cathode current collector.

As described above, the electrode catalyst according to the embodiment of the present invention can effectively impregnate the proton pass phosphoric acid into the pores of the catalyst carrier (conductive carrier). Therefore, in the electrode using such an electrode catalyst, the effect of improving the power generation characteristics of the acid-doped fuel cell can be obtained by increasing the catalytic reaction area. Further, in the acid-doped fuel cell using the electrode according to the embodiment of the present invention, there is an effect that the aging (conditioning) time of initial power generation activation can be greatly shortened.

In addition, in the fuel cell electrode according to the embodiment of the present invention, since the doping catalyst and the undoped catalyst have an electrode catalyst layer uniformly dispersed, it is possible to trap acid leached from the polymer electrolyte membrane over time. Since the space for gas diffusion in the electrode catalyst layer can be maintained, the degradation of power generation characteristics is reduced and the durability is improved.

Hereinafter, although an Example is given and this invention is demonstrated in more detail, this invention is not limited by the following Example.

Preparation Example 1 Preparation of Acid-impregnated Electrode Catalyst

A carbon carrier (BET specific surface area: about 60 m ² / g) obtained by partially graphitizing VULCAN XC-72 (manufactured by Cabot Co., Ltd.) was used as a conductive carrier, and thus a platinum-cobalt alloy (weight ratio of platinum to cobalt = 10: An electrode catalyst carrying 1) as catalyst particles was used as an acid-impregnated electrode catalyst (undoped catalyst). The platinum loading of this undoped electrode catalyst was about 50% by weight based on the weight of the carbon carrier.

Preparation Example 2 Preparation of Acid Impregnated Electrode Catalyst

5 g of the undoped electrode catalyst obtained in Production Example 1 was dispersed in 100 g of 85% by weight aqueous solution of phosphoric acid, and after stirring, the mixture was kept in a vacuum apparatus for 1 hour to impregnate the phosphoric acid in the pores of the carbon carrier. Then, heat processing was performed at 150 degreeC. Thereafter, the electrode catalyst in which phosphoric acid was impregnated with the carbon carrier was washed with water, filtered and dried to obtain a phosphoric acid impregnation catalyst (dope catalyst).

In order to specify the amount of phosphoric acid impregnated in the obtained dope catalyst, quantitative analysis of phosphoric acid impregnated was performed using inductively coupled plasma emission spectroscopy. An inductively coupled plasma emission spectrophotometer (SPS-1700HVR) manufactured by SIA INA Technology Co., Ltd. was used as the analyzer.

As a result, the amount of phosphoric acid impregnated in the doping catalyst was about 0.73% by weight based on the weight of the carbon carrier.

Example 1

An electrode for a fuel cell was manufactured using the dope catalyst and the undoped catalyst prepared in the preparation example.

First, 0.8 g of dope catalyst and 0.2 g of undoped catalyst (ratio of doping catalyst weight to weight of undoped catalyst = 80:20) were used, and 1.0 g of polyvinylidene fluoride (PVdF) binder resin was added N, N-dimethylformamide. (DMF) was added to a solution (PVdF 5% by weight solution) dissolved in 19 g, and dispersed in a magnetic stirrer for about 10 minutes to prepare an electrode slurry.

The electrode slurry is coated on a gas diffusion layer (GDL 34BC manufactured by SGL Carbon, Inc.) with a microporous layer, using a doctor blade, and preliminarily dried at 60 ° C. for about 20 minutes, and dried at 150 ° C. for about 30 minutes to form an electrode catalyst layer. To form an electrode.

Polybenzimidazole (PBI) (intrinsic viscosity 0.7-0.9 dL / g as measured by dissolving in sulfuric acid at a concentration of 30% by weight) as a polymer electrolyte membrane was dissolved in 10% by weight of N-methyl-2-pi A dried PBI membrane (thickness: 35 μm) obtained by casting a Lollidon (NMP) solution was immersed in an 85 wt% aqueous solution of phosphoric acid, heated at 60 ° C. for 2 hours, to obtain a phosphoric acid doped PBI membrane, which was swollen by phosphoric acid. The thickness of the PBI film after swelling was about 100 μm and the doping amount of phosphoric acid was about 350 wt% relative to 100 wt% of the PBI film.

The electrode prepared as described above was cut into a square having a width of 5 cm and used as an anode and a cathode. The polymer electrolyte membrane cut into squares having a width of 7 cm was sandwiched so that the anode and cathode catalyst layers were in contact with the polymer electrolyte membrane on both sides thereof, thereby producing a membrane electrode assembly 100 as shown in FIG.

Comparative Example 1

The electrode and membrane electrode assembly (100) were prepared using the same method as described in Example 1, except that 1.0 g of the undoped catalyst (100 wt% of the undoped catalyst) obtained in Preparation Example 1 was not used. ) Was produced.

Comparative Example 2

Electrode and membrane electrode assembly 100 were prepared using the same method as described in Example 1, except that 1.0 g (100 wt% of doping catalyst) obtained in Preparation Example 2 was used without using an undoped catalyst. Was produced.

<Production of fuel cells>

)으로 이루어진 개스킷(두께　200㎛)을　설치한　다음, 이것을　가스　유로가 딸린 카본　세퍼레이터로　샌드위치하였다. 이것을 다시 집전판으로 샌드위치하고 양단을　스테인레스강으로 이루어진 엔드　플레이트로　샌드위치한 후, 조임 압력이　5×10⁵ Pa이 되도록 토크　렌치로　볼트를 단단히　조여서 테스트 셀을 제작하였다.Polytetrafluoroethylene (TEFRON) around the electrode of the membrane electrode assembly 100

Gaskets (thickness: 200 mu m) were formed and sandwiched with a carbon separator with a gas flow path. This was again sandwiched by a current collector plate and sandwiched at both ends by an end plate made of stainless steel, and a test cell was manufactured by tightening a bolt with a torque wrench so that the tightening pressure was 5 × 10 ⁵ Pa.

<Test of power generation characteristics of fuel cell>

While purging the test cell with nitrogen purge, the temperature was raised to 150 ° C., and the flow rate was controlled from the bomb so that the hydrogen gas utilization rate and oxygen gas utilization rate were 80% and 50%, respectively, as pure hydrogen gas as anode and fuel as oxidant in cathode. The test cells were introduced directly through the mass flow (without humidifier conditions and without humidification). In order to measure the polarization characteristics and continuous power generation characteristics of the power generation, the continuous power generation characteristics were 0.3A / cm ² constant current operation using an electronic load device (ELZ-303 manufactured by the Institute of Measurement Technology). The change was investigated.

3 is a current-voltage characteristic graph showing the power generation characteristics of the test cell using the membrane electrode assembly in Example 1 and Comparative Example 1, Figure 4 is a membrane electrode assembly of Example 1, Comparative Example 1 and Comparative Example 2 It is a graph showing the change over time of the continuous power generation characteristics of the test cell used.

As can be seen from FIG. 3, MEA () using the electrode of Example 1 exhibits superior power generation characteristics as compared to MEA using the untreated electrode of Comparative Example 1 (□). This is presumably because an effective proton path is formed by uniformly dispersing the acid in the catalyst layer by performing a phosphoric acid treatment step on the catalyst, whereby a characteristic improvement is obtained.

As can be seen in FIG. 4, the MEA () using the fuel cell electrode produced in Example 1 had a higher voltage value than the MEA (□) using the untreated electrode produced in Comparative Example 1. The initial start-up (conditioning) time was shortened from about 250 hours (Comparative Example 1) to about 50 hours (Example 1) (not shown in FIG. 5, but the time required for the voltage to rise to 660 mV is the case of Comparative Example 1 Was about 250 hours, and in Example 1 it was about 50 hours). This indicates that the MEA produced in Example 1 has improved power generation characteristics compared to the MEA produced in Comparative Example 1, and the initial start-up (conditioning) time is reduced to about 1/5.

The MEA produced in Example 1 is slightly inferior to the initial start (conditioning) of the power generation characteristics, compared to the MEA (Δ) produced with the electrode (Comparative Example 2) using 100% by weight of the doped catalyst subjected to the phosphoric acid treatment step. As a result, it has been confirmed that the power generation characteristics are maintained for a longer period of time over time.

In this way, by performing a phosphoric acid treatment step on the catalyst in advance, an effective proton pass is formed by homogenizing the acid distribution in the catalyst layer, so that the characteristic improvement can be obtained, and since the optimum amount of acid in the catalyst layer is controlled from the beginning, Shortening of the shunting time was made possible and the difference of the characteristic was achieved.

In the long term, the acid doped in the polymer electrolyte membrane leaches into the catalyst layer and is subsequently discharged to the outside of the MEA. In that case, however, as is apparent from FIG. Since the conductive carrier of the undoped catalyst has an allowance to impregnate the acid, it is possible to trap the acid in the MEA, to prevent the acid from flowing out, and to have a complex function that does not damage the pores for gas diffusion. Therefore, it is estimated that durability can be improved rather than such MEA structure.

As described above, in the fuel cell electrode using the catalyst obtained in the phosphoric acid impregnation treatment step, the distribution of phosphoric acid in the electrode catalyst layer becomes uniform, and the active area of the catalyst increases (acid uniform distribution in the carrier carbon pores), thereby improving the characteristics and It was possible to reach the equilibrium voltage quickly at the beginning of power generation. In addition, by using the electrode produced by mixing the catalyst obtained in the phosphoric acid impregnation process with the untreated catalyst, the function of trapping phosphoric acid leached from the membrane in the carrier carbon of the untreated catalyst in the long term can also be expressed to improve durability.

As mentioned above, although preferred embodiment of this invention was described in detail, referring an accompanying drawing, this invention is not limited to this example. It is apparent that any person having ordinary knowledge in the technical field to which the present invention belongs can conceive various modifications or modifications within the scope of the technical idea described in the claims, and these are naturally the technical scope of the present invention. It is understood to belong to.

For example, in the above embodiment, the case where the doped catalyst and the undoped catalyst are uniformly dispersed in the electrode catalyst layer has been described. However, even when the doped catalyst and the undoped catalyst are uniformly dispersed in the electrode catalyst layer, the dispersion is uniformly performed. Although performance is inferior compared with the case where it is, the effect concerning embodiment of this invention can be exhibited to some extent. The electrode catalyst layer may have a laminated structure of a first catalyst layer made of an undoped catalyst positioned on the polymer electrolyte membrane side and a second catalyst layer made of a doped catalyst deposited on the first catalyst layer.

1: Electrode for Fuel Cell
3: polymer electrolyte membrane
5: electrode catalyst layer
10: acid-impregnated electrode catalyst (undoped catalyst)
11: conductive carrier
13: catalyst particles
15: acid-impregnated conductive carrier
20: acid impregnated electrode catalyst (dope catalyst)
30: first gas diffusion layer
40: second gas diffusion layer
100: membrane electrode assembly.

Claims (17)

An electrode for a fuel cell comprising an electrode catalyst layer,
The electrode catalyst layer comprises an electrode catalyst comprising a conductive carrier and catalyst particles supported on the conductive carrier,
The electrode catalyst includes an acid impregnated electrode catalyst in which an acid component having proton conductivity is impregnated in the conductive carrier and an acid impregnated electrode catalyst in which the acid component is not impregnated in the conductive carrier. The electrode for a fuel cell of claim 1, wherein the electrode catalyst layer has a mixing ratio of the weight of the acid-impregnated electrode catalyst to the weight of the acid-impregnated electrode catalyst = 5 to 95: 95 to 5 when the electrode catalyst layer is formed. The fuel cell electrode according to claim 1, wherein the conductive carrier is a carbon material. The method of claim 1, wherein the catalyst particles are platinum (Pt), gold (Au), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru), cobalt (Co), iron (Fe) , Fuel cell electrode including at least one metal selected from the group consisting of lead (Pb), manganese (Mn), chromium (Cr), gallium (Ga), tin (Sn), molybdenum (Mo), and vanadium (V) . The fuel cell of claim 1, wherein the acid is at least one acid selected from the group consisting of phosphoric acid, phosphoric acid derivatives, phosphonic acid, phosphonic acid derivatives, phosphinic acid, phosphinic acid derivatives, sulfuric acid, sulfuric acid derivatives, sulfonic acid and sulfonic acid derivatives. electrode. The method of claim 1, wherein the electrode catalyst layer is polytetrafluoroethylene (PTFE), poly (vinylidene fluoride) (PVDF), tetrafluoroethylene-hexafluoroethylene copolymer, tetrafluoroethylene-hexafluoro A fuel further comprising at least one binder resin selected from the group consisting of propylene copolymer, polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (ETFE), styrene butadiene rubber (SBR), and polyurethane Battery electrode. Applying a composition for an electrode catalyst layer comprising an acid-impregnated electrode catalyst in which an acid component having proton conductivity is impregnated in the conductive carrier and an acid-impregnated electrode catalyst in which the acid component is not impregnated in the conductive carrier; And
A method of manufacturing an electrode for a fuel cell according to any one of claims 1 to 6, comprising forming the electrode catalyst layer by drying the applied composition for the catalyst layer. The method of claim 7, wherein the mixing ratio of the weight of the acid-impregnated electrode catalyst to the weight of the acid-impregnated electrode catalyst is 5 to 95:95 to 5 in the catalyst layer composition. The method of claim 7, wherein the acid impregnated electrode catalyst,
And dispersing the acid impregnated electrode catalyst in the acid component to perform vacuum heat treatment. The method of claim 7, wherein the vacuum heat treatment is performed at a temperature of 100 ~ 150 ℃. The method for manufacturing an electrode for a fuel cell according to claim 7, wherein the conductive carrier is a carbon material. The method of claim 8, wherein the catalyst particles, platinum (Pt), gold (Au), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru), cobalt (Co), iron (Fe) , Fuel cell electrode including at least one metal selected from the group consisting of lead (Pb), manganese (Mn), chromium (Cr), gallium (Ga), tin (Sn), molybdenum (Mo), and vanadium (V) Manufacturing method. The fuel cell of claim 7, wherein the acid is at least one acid selected from the group consisting of phosphoric acid, phosphoric acid derivatives, phosphonic acid, phosphonic acid derivatives, phosphinic acid, phosphinic acid derivatives, sulfuric acid, sulfuric acid derivatives, sulfonic acid and sulfonic acid derivatives. Method of manufacturing the electrode. The method of claim 7, wherein the electrode catalyst layer is polytetrafluoroethylene (PTFE), poly (vinylidene fluoride) (PVDF), tetrafluoroethylene-hexafluoroethylene copolymer, tetrafluoroethylene-hexafluoro A fuel further comprising at least one binder resin selected from the group consisting of propylene copolymer, polychlorotrifluoroethylene (PCTFE), tetrafluoroethylene-ethylene copolymer (ETFE), styrene butadiene rubber (SBR), and polyurethane Method for producing a battery electrode. The method of claim 7, wherein the acid component is at least one acid selected from the group consisting of phosphoric acid, phosphoric acid derivatives, phosphonic acid, phosphonic acid derivatives, phosphinic acid, phosphinic acid derivatives, sulfuric acid, sulfuric acid derivatives, sulfonic acid and sulfonic acid derivatives The manufacturing method of the electrode for fuel cells which is aqueous solution of. A fuel cell membrane electrode assembly (MEA) comprising a cathode and an anode positioned opposite to each other, and a solid electrolyte membrane positioned between the cathode and the anode,
A membrane electrode assembly, wherein the solid electrolyte membrane comprises a basic polymer doped with an acid component, and at least one of the cathode electrode and the anode electrode is an electrode for a fuel cell according to any one of claims 1 to 6. A fuel cell comprising a membrane electrode assembly comprising the electrode for fuel cells according to any one of claims 1 to 6.

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