KR100778438B1 - Cathode catalyst for fuel cell, membrane-electrode assembly for fuel cell comprising same and fuel cell system comprising same - Google Patents

Abstract

A cathode catalyst for a fuel cell, a membrane electrode assembly containing the cathode catalyst, and a fuel cell system containing the membrane electrode assembly are provided to improve the activity and selectivity to the reduction of an oxidizing agent. A cathode catalyst comprises a carbon-based material; and 5-85 wt% of M-Ce supported on the carbon-based material, wherein M is at least one metal selected from the group consisting of Ru, Rh, Pd, Os, Ir and their mixture. Preferably M-Ce comprises 10-90 atom% of M and 10-90 atom% of Ce; and the carbon-based material is at least one selected from the group consisting of graphite, denka black, ketchen black, acetylene black, carbon nanotube, carbon nanofiber, carbon nanowire, carbon nanoball, activated carbon, and their mixture.

Description

Cathode catalyst for fuel cell, membrane-electrode assembly and fuel cell system for fuel cell comprising same {CATHODE CATALYST FOR FUEL CELL, MEMBRANE-ELECTRODE ASSEMBLY FOR FUEL CELL COMPRISING SAME AND FUEL CELL SYSTEM COMPRISING SAME}

1 is a view schematically showing a cross section of a membrane-electrode assembly for a fuel cell according to an embodiment of the present invention.

2 schematically illustrates the structure of a fuel cell system according to an embodiment of the invention.

Figure 3 is a graph showing the X-ray diffraction peaks of the catalyst powder prepared according to Example 1 of the present invention.

4 is a graph showing the results of catalyst activity measured using Rotating Disk Electrode (RDE) of a fuel cell using a cathode catalyst for fuel cells prepared according to Example 1 and Reference Example 1 of the present invention.

[Industrial use]

The present invention relates to a cathode catalyst for a fuel cell, a membrane-electrode assembly for a fuel cell including the same, and a fuel cell system including the same. More particularly, the present invention provides excellent activity and selectivity for a reduction reaction of an oxidant. A cathode-cathode catalyst for a fuel cell capable of improving the performance of a fuel cell membrane-electrode assembly and a fuel cell system, and a membrane-electrode assembly for a fuel cell and a fuel cell system comprising the same.

[Prior art]

A fuel cell is a power generation system that converts chemical reaction energy of hydrogen and oxidant contained in hydrogen or hydrocarbon-based material directly into electrical energy.

Representative examples of the fuel cell include a polymer electrolyte fuel cell (PEMFC) and a direct oxidation fuel cell (Direct Oxidation Fuel Cell). When methanol is used as a fuel in the direct oxidation fuel cell, it is called a direct methanol fuel cell (DMFC).

In general, polymer electrolyte fuel cells have the advantages of high energy density and high output, but they require attention to the handling of hydrogen gas and fuels for reforming methane, methanol and natural gas to produce hydrogen, fuel gas. There is a problem that requires additional equipment such as a reforming device.

In contrast, the direct oxidation fuel cell has a slower reaction rate, which results in lower energy density, lower power, and a larger amount of electrode catalyst than the polymer electrolyte type, but it is easy to handle liquid fuel and has a low operating temperature. In particular, it has the advantage of not requiring a fuel reformer.

In such a fuel cell system, the stack that substantially generates electricity is comprised of several to several dozen unit cells consisting of a membrane-electrode assembly (MEA) and a separator (or bipolar plate). It has a laminated structure. The membrane-electrode assembly is called an anode electrode (also called "fuel electrode" or "oxide electrode") and a cathode electrode (also called "air electrode" or "reduction electrode") with a polymer electrolyte membrane including a hydrogen ion conductive polymer therebetween. Has a bonded structure.

It is an object of the present invention to provide a cathode catalyst for a fuel cell having excellent activity and selectivity for the reduction reaction of an oxidant.

Yet another object of the present invention is to provide a membrane-electrode assembly for a fuel cell comprising the cathode catalyst.

Still another object of the present invention is to provide a fuel cell system comprising the membrane-electrode assembly for a fuel cell of the present invention.

In order to achieve the above object, the present invention is selected from the group consisting of carbon-based material and M-Ce supported on the carbon-based material (wherein M is Ru, Rh, Pd, Os, Ir, Pt, and combinations thereof) Provided is a cathode catalyst for a fuel cell comprising at least one metal).

The present invention also includes an anode electrode and a cathode electrode positioned to face each other and a polymer electrolyte membrane positioned between the anode and the cathode electrode, the cathode electrode includes a conductive electrode substrate and a catalyst layer formed on the electrode substrate, The catalyst layer provides a membrane-electrode assembly for a fuel cell comprising the cathode catalyst of the present invention.

The present invention also provides a fuel cell system including an electricity generation unit including the membrane-electrode assembly and the separator of the present invention, a fuel supply unit supplying fuel to the electricity generation unit, and an oxidant supply unit supplying an oxidant to the electricity generation unit. do.

Hereinafter, the present invention will be described in more detail.

A fuel cell is a power generation system that obtains electrical energy through oxidation of a fuel and reduction of an oxidant. An oxidation reaction of a fuel occurs at an anode electrode and a reduction reaction of an oxidant occurs at a cathode electrode.

Catalysts capable of promoting the oxidation reaction of the fuel and the reduction reaction of the oxidant are used for the catalyst layers of the anode electrode and the cathode electrode, and platinum-ruthenium is typically used for the catalyst layer of the anode electrode and platinum is used for the catalyst layer of the cathode electrode.

However, the platinum used as the cathode catalyst lacks the selectivity for the reduction reaction of the oxidant, and is depolarized by the fuel that has passed through the electrolyte membrane to the cathode region in a direct oxidation fuel cell. There is a problem of deactivation, and attention is focused on a catalyst that can replace platinum.

The cathode catalyst of the present invention is to solve the above problems, M-Ce (where M is Ru, Rh, Pd, Os, Ir, Pt, and a combination thereof supported on the carbon-based material and the carbon-based material At least one metal selected from the group). In the catalyst, M-Ce is an active material having activity against a reduction reaction of an oxidizing agent, and the carbonaceous material corresponds to a carrier supporting the M-Ce.

In the active substance M-Ce, M is at least one metal selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, and a combination thereof, and has a high activity for the reduction reaction of the oxidant. However, there is a problem that oxygen in the air is easily adsorbed to the metal as described above, and the adsorbed oxygen makes it difficult to reduce the oxidizing agent by blocking an active center where the reducing reaction of the oxidizing agent occurs.

Ce has a strong reducing power because it can have a variety of oxidation water, it shows an excellent activity for the reduction reaction of the oxidizing agent. In addition, by combining with the metals, by preventing the oxygen in the air to be adsorbed to the metal, it improves the activity of the reduction of the oxidant of the metals. In addition, the compound formed by combining Ce with the metals includes many defects, and since such defects may have more active centers for the reduction reaction of the oxidizing agent, Ce and the metals are formed The compound can exhibit more excellent activity by synergism.

After all, M-Ce, an active material consisting of Ce and at least one metal selected from the group consisting of Ru, Rh, Pd, Os, Ir, Pt, and combinations thereof, has excellent activity and selectivity for the reduction reaction of the oxidizing agent. It can be effectively used as a cathode catalyst for fuel cells. In particular, due to the excellent selectivity to the reduction reaction of the oxidant, it can be used more effectively in a direct oxidation fuel cell in which crossover of fuel is a problem.

In the M-Ce, the content of M is 10 to 90 atomic%, the content of Ce is preferably 10 to 90 atomic%. If the content of M exceeds 90 atomic%, the selectivity of the catalyst is inferior. When the content of M is less than 10 atomic%, the catalytic activity is inferior. If the content of Ce exceeds 90 atomic%, the size of the catalyst particles becomes too large, and if the content of Ce is less than 10 atomic%, the catalytic activity is inferior.

The M-Ce is used by being supported on a carbon-based material. This is because when M-Ce is used by itself, there is a problem in that the electrical conductivity is insufficient, and particles are agglomerated with each other to obtain particles of small size. By supporting the carbon-based material, the electrical conductivity of the catalyst can be improved, and the size of the catalyst particles can be reduced to increase the surface area per unit mass, that is, the specific surface area. By increasing the specific surface area, the activity per unit mass of the catalyst can be increased.

Any carbon-based material may be used as the carrier, but graphite, denka black, ketjen black, carbon nanotubes, carbon nanofibers, carbon nanowires, and the like may be preferably used.

The amount of M-Ce supported on the carbon-based material is preferably 5 to 85% by weight based on the total weight of the catalyst. If the supported amount is less than 5% by weight, there is a problem that the activity per unit mass of the catalyst is excessively lowered. If the supported amount is more than 85% by weight, the supported catalyst is agglomerated to form agglomerates, which is not preferable because the catalyst activity is lowered.

M-Ce may be present not only crystalline as well as amorphous on the carbon-based material carrier. Preferably, crystalline M-Ce and amorphous M-Ce coexist on the carrier. This is because a large number of defects exist in the region where the crystalline and the amorphous contact, since there are many active centers in such a defect.

The cathode catalyst of the present invention exhibits very good activity and selectivity for the oxidant reduction reaction, and exhibits about twice the performance of Ru-Se / C, which is a typical selective catalyst.

The cathode catalyst of the present invention described above is a catalyst comprising dissolving a water-soluble salt of metal M and a water-soluble salt of Ce in a solvent, adding and mixing a carbonaceous material to the prepared solution, and drying and heat-treating the prepared mixture. It can be manufactured by the manufacturing method.

First, a water-soluble salt of metal M and a water-soluble salt of Ce are dissolved in a solvent, and a carbon-based material is added to the prepared solution and mixed. Water, ethanol or methanol may be preferably used as the solvent, and M chloride, M acetylacetonate and M nitrozylnitrate may be used as the water-soluble salt of the metal M. As the water-soluble salt of Ce, cerium nitrate may be preferably used.

Next, the mixture prepared through the above process is dried. It is preferable to perform drying at the temperature of 90 degreeC in a vacuum state.

Finally, after the drying step, heat treatment is performed. It is preferable to perform heat processing at the temperature of 200-300 degreeC in hydrogen atmosphere.

The cathode catalyst for a fuel cell of the present invention can be prepared by the above-described method, and the cathode catalyst of the present invention prepared by the above method exhibits excellent activity even when the active material is crystalline as well as amorphous on the carrier. Can be.

The present invention also provides a fuel cell membrane-electrode assembly comprising the cathode catalyst for fuel cell of the present invention as described above.

The membrane-electrode assembly of the present invention includes an anode electrode and a cathode electrode positioned to face each other and a polymer electrolyte membrane positioned between the anode and the cathode electrode, wherein the anode electrode and the cathode electrode are formed of an electrode substrate and a conductive substrate. It includes a catalyst layer formed on the electrode substrate.

1 is a view schematically showing a cross section of the membrane-electrode assembly 131 according to an embodiment of the present invention. Hereinafter, the membrane-electrode assembly 131 of the present invention will be described with reference to the drawings.

The membrane-electrode assembly 131 generates electricity through oxidation of a fuel and reduction of an oxidant, and one or several are stacked and mounted in a stack.

A reduction reaction of the oxidant occurs in the catalyst layer 53 of the cathode electrode, and the catalyst layer includes the cathode catalyst for fuel cell of the present invention. The cathode catalyst shows excellent activity and selectivity for the reduction reaction of the oxidant, thereby improving performance of the cathode electrode 5 and the membrane-electrode assembly 131 including the same.

In the anode layer of the catalyst layer 33, the oxidation reaction of the fuel occurs, and includes a catalyst for promoting the reaction. Participating in the reaction of the fuel cell, anything that can be used as a catalyst can be used, and a representative example thereof is platinum-based Catalysts can be used.

As the platinum-based catalyst, platinum, ruthenium, osmium, platinum-ruthenium alloy, platinum-osmium alloy, platinum-palladium alloy, platinum-M alloy (M is Ga, Ti, V, Cr, Mn, Fe, Co, Ni, At least one catalyst selected from the group consisting of Cu, Zn, Sn, Mo, W, Rh, and combinations thereof, and combinations thereof.

As described above, the anode electrode and the cathode electrode may use the same material, but in order to prevent the catalyst poisoning caused by CO generated during the anode electrode reaction in the direct oxidation fuel cell, a platinum-ruthenium alloy catalyst is used as the anode. It is more preferable as an electrode catalyst. Specific examples include Pt, Pt / Ru, Pt / W, Pt / Ni, Pt / Sn, Pt / Mo, Pt / Pd, Pt / Fe, Pt / Cr, Pt / Co, Pt / Ru / W, Pt / Ru At least one selected from the group consisting of / Mo, Pt / Ru / V, Pt / Fe / Co, Pt / Ru / Rh / Ni, Pt / Ru / Sn / W, and a combination thereof may be used.

The catalyst may be used as the catalyst itself (black), or may be supported on a carrier. As the carrier, carbonaceous materials such as graphite, denka black, ketjen black, acetylene black, carbon nanotube, carbon nanofiber, carbon nanowire, carbon nanoball or activated carbon may be used, or alumina, silica, zirconia, Inorganic fine particles such as titania may be used, but carbon-based materials are generally used.

Catalyst layers 33 and 53 of the anode electrode and the cathode electrode may include a binder, it is preferable to use a polymer resin having hydrogen ion conductivity as the binder, more preferably sulfonic acid groups, carboxyl in the side chain Any polymer resin having at least one cation exchange group selected from the group consisting of acid groups, phosphoric acid groups, phosphonic acid groups, derivatives thereof, and combinations thereof can be used.

Preferably, a fluorine polymer, a benzimidazole polymer, a polyimide polymer, a polyetherimide polymer, a polyphenylene sulfide polymer, a polysulfone polymer, a polyether sulfone polymer, a polyether ketone polymer, a polyether At least one hydrogen ion conductive polymer selected from the group consisting of ether ketone polymers, polyphenylquinoxaline polymers, and combinations thereof, and more preferably poly (perfluorosulfonic acid), poly ( Perfluorocarboxylic acid), copolymers of tetrafluoroethylene and fluorovinyl ether containing sulfonic acid groups, defluorinated sulfide polyether ketones, aryl ketones, poly (2,2'-m-phenylene) -5 , 5'-bibenzimidazole (poly (2,2 '-(m-phenylene) -5,5'-bibenzimidazole), poly (2,5-benzimidazole), and combinations thereof Being at least Of it can be used in that it comprises a hydrogen-ion conductive polymer.

The binder may be used in the form of a single substance or a mixture, and may also be optionally used with a nonconductive polymer for the purpose of further improving adhesion to the polymer electrolyte membrane. It is preferable to adjust the usage-amount so that it may be suitable for a purpose of use.

Examples of the nonconductive polymer include polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoro alkylvinyl ether copolymer (PFA), and ethylene / tetrafluoro Ethylene / tetrafluoroethylene (ETFE), ethylenechlorotrifluoro-ethylene copolymer (ECTFE), polyvinylidene fluoride, copolymer of polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP), dode More preferred is at least one selected from the group consisting of silbenzenesulfonic acid, sorbitol, and combinations thereof.

The electrode substrates 31 and 51 of the anode electrode and the cathode electrode serve to make a reaction source, that is, a fuel and an oxidant, easily accessible to the catalyst layers 31 and 51, and the electrode substrates 31 and 51 are conductive. The surface of a fabric formed of a porous film or polymer fiber composed of carbon paper, carbon cloth, carbon felt or metal cloth (fibrous metal cloth) The metal film is formed on (metalized polymer fiber)) may be used, but is not limited thereto.

In addition, it is preferable to use a water-repellent treatment with a fluorine-based resin as the electrode base material because it can prevent the reactant diffusion efficiency from being lowered by water generated when the fuel cell is driven. Examples of the fluorine-based resin include polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl hexafluoropropylene, polyperfluoroalkyl vinyl ether, polyperfluorosulfonyl fluoride alkoxy vinyl ether, and fluorinated ethylene propylene. (Fluorinated ethylene propylene), polychlorotrifluoroethylene or copolymers thereof can be used.

In addition, a microporous layer may be further included to enhance the reactant diffusion effect in the electrode substrate. These microporous layers are generally conductive powders having a small particle diameter, such as carbon powder, carbon black, acetylene black, activated carbon, carbon fiber, fullerene, carbon nanotubes, carbon nanowires, and carbon nanohorns. -horn or carbon nano ring.

The microporous layer is prepared by coating a composition comprising a conductive powder, a binder, and a solvent on the electrode substrate. The binder may be polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, polyperfluoroalkyl vinyl ether, polyperfluorosulfonyl fluoride, alkoxy vinyl ether, polyvinyl alcohol, cellulose acetate or These copolymers etc. can be used preferably.

As the solvent, alcohols such as ethanol, isopropyl alcohol, n-propyl alcohol, butyl alcohol, water, dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, etc. may be preferably used. The coating process may be screen printing, spray coating, or coating using a doctor blade according to the viscosity of the composition, but is not limited thereto.

As the polymer electrolyte membrane 1, a polymer having an ion exchange function of transferring hydrogen ions generated in the catalyst layer 33 of the anode electrode to the catalyst layer 53 of the cathode electrode, and having excellent hydrogen ion conductivity may be used.

Representative examples thereof include a polymer resin having at least one cation exchange group selected from the group consisting of sulfonic acid groups, carboxylic acid groups, phosphoric acid groups, phosphonic acid groups, derivatives thereof, and combinations thereof in the side chain.

Representative examples of the polymer resin include a fluorine polymer, a benzimidazole polymer, a polyimide polymer, a polyetherimide polymer, a polyphenylene sulfide polymer, a polysulfone polymer, a polyether sulfone polymer and a polyether ketone At least one selected from the group consisting of a polymer, a polyether-etherketone-based polymer, a polyphenylquinoxaline-based polymer, and a combination thereof, and more preferably poly (perfluorosulfonic acid), poly (purple) Fluorocarboxylic acid), copolymers of tetrafluoroethylene and fluorovinyl ether containing sulfonic acid groups, defluorinated sulfide polyether ketones, aryl ketones, poly (2,2'-m-phenylene) -5, 5'-bibenzimidazole (poly (2,2 '-(m-phenylene) -5,5'-bibenzimidazole), poly (2,5-benzimidazole), and combinations thereof At least one It may generally have a thickness from 10 -200㎛ the polymer electrolyte membrane.

In the hydrogen ion conductive group of the hydrogen ion conductive polymer, H may be substituted with Na, K, Li, Cs or tetrabutylammonium. When H is replaced by Na in an ion exchange group at the side chain terminal, NaOH is substituted when preparing a catalyst composition, and tetrabutylammonium hydroxide is used when tetrabutylammonium is used, and K, Li or Cs is also a suitable compound. It can be substituted using. Since this substitution method is well known in the art, detailed description thereof will be omitted.

The present invention also provides a fuel cell system comprising the membrane-electrode assembly of the present invention as described above.

The fuel cell system of the present invention includes at least one electricity generator, a fuel supply and an oxidant supply.

The electricity generating portion includes a membrane-electrode assembly and a separator (also called bipolar plate). The membrane-electrode assembly includes a polymer electrolyte membrane and cathode and anode electrodes existing on both sides of the polymer electrolyte membrane. The electricity generation unit serves to generate electricity through the oxidation reaction of the fuel and the reduction reaction of the oxidant.

The fuel supply unit serves to supply fuel to the electricity generation unit, and the oxidant supply unit serves to supply an oxidant such as oxygen or air to the electricity generation unit.

In the present invention, the fuel may include hydrogen or hydrocarbon fuel in gas or liquid state. Representative examples of the hydrocarbon fuel include methanol, ethanol, propanol, butanol or natural gas.

The fuel cell system of the present invention can be employed without limitation in Polymer Electrolyte Membrane Fuel Cell (PEMFC), Direct Oxidation Fuel Cell, and Mixed Reactant Fuel Cell. Direct oxidation fuel cells are more preferred.

A schematic structure of a fuel cell system 100 according to an embodiment of the present invention is shown in FIG. 2, which will be described in more detail with reference to the following. 2 shows a system for supplying fuel and oxidant to the electricity generation unit 130 using pumps 151 and 171, but the membrane-electrode assembly 131 for fuel cells of the present invention is limited to such a structure. Of course, it can be used in a fuel cell system having a structure using a diffusion method without using a pump.

The fuel cell system 100 includes a stack 110 having at least one electricity generator 130 for generating electrical energy through an oxidation reaction of a fuel and a reduction reaction of an oxidant, and a fuel supply unit 150 for supplying the fuel. ) And an oxidant supply unit 170 for supplying an oxidant to the electricity generation unit 130.

The fuel supply unit 150 supplying the fuel includes a fuel tank 153 for storing fuel and a fuel pump 151 connected to the fuel tank 153. The fuel pump 151 serves to discharge the fuel stored in the fuel tank 153 by a predetermined pumping force.

The oxidant supply unit 170 for supplying an oxidant to the electricity generating unit 130 of the stack 110 includes at least one oxidant pump 171 that sucks the oxidant with a predetermined pumping force.

The electricity generating unit 130 is a membrane-electrode assembly 131 for oxidizing and reducing a fuel and an oxidant and a separator (bipolar plate) 133 and 135 for supplying fuel and an oxidant to both sides of the membrane-electrode assembly 131. ), The electricity generating unit 130 is at least one gather to constitute a stack (110).

Hereinafter, preferred examples and reference examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention and the present invention is not limited to the following examples.

(Example 1)

2.5 g of Ce (No ₃ ) ₃ , 1.5 g of RuCl ₃ .H ₂ O, 1 g of ketjenblack and 5 ml of a solvent of 5 ml of water are mixed for 2 hours and dried at 80 ° C. The dried product is placed in a vacuum atmosphere at 200 ° C. for 24 hours and then dried at 90 ° C. The dried product was heat-treated at 250 ° C. for 3 hours in a hydrogen atmosphere to prepare a cathode catalyst powder (Ru-Ce / C) for a fuel cell. The content of Ru in the prepared Ru-Ce was 68 atomic%, and the content of Ce was 32 atomic%. In addition, the loading amount of Ru-Ce was 71% by weight based on the total weight of the catalyst.

(Reference Example 1)

0.5 g of ruthenium carbonyl, 0.03 g of Se, 1 g of carbon, and 150 ml of toluene, a solvent, are mixed at 100 ° C. for 24 hours. The mixture is filtered and dried at 80 ° C. to obtain a powder. The powder was heat-treated at 250 ° C. for 3 hours under a hydrogen atmosphere to obtain a cathode catalyst powder (Ru-Se / C) for a fuel cell.

X-ray diffraction peaks of the catalyst powder prepared according to Example 1 were measured and the results are shown in FIG. 3. It is a graph showing an analysis result (XRD). X-ray diffraction peaks were measured using CuK rays. As can be seen in Figure 3, the cathode catalyst prepared in Example 1 has a low crystallinity region. In addition, the cathode catalyst drawn in Example 1 has a particle size of 3 to 4 nm.

The catalytic activity of the catalysts prepared according to Example 1 and Reference Example 1 was measured by Rotating Disk Electrode (RDE). In the RDE measurement, AgCl was used as a reference electrode, Pt was used as a counter electrode, and oxygen-saturated sulfuric acid was bubbled by bubbling oxygen gas in a 0.5 M sulfuric acid solution for 2 hours. Using the solution, it was measured at a scan rate of 10 mV / s and a rotating speed of 2000 rpm. The results are shown in FIG. As shown in Figure 4, it can be seen that the catalyst of Example 1 shows a similar catalytic activity as the catalyst of Reference Example 1.

The cathode catalyst for a fuel cell of the present invention is excellent in activity and selectivity for a reduction reaction of an oxidant, and has an advantage of improving performance of a fuel cell membrane-electrode assembly and a fuel cell system including the same.

Claims (13)

Carbon-based materials; And A cathode catalyst for a fuel cell comprising M-Ce (where M is at least one metal selected from the group consisting of Ru, Rh, Pd, Os, Ir, and combinations thereof) supported on the carbonaceous material. The method of claim 1, The content of M in the M-Ce is 10 to 90 atomic%, the content of Ce is 10 to 90 atomic% of the cathode catalyst for a fuel cell. The method of claim 1, The supported amount of the M-Ce is 5 to 85% by weight based on the total weight of the catalyst cathode catalyst for fuel cells. The method of claim 1, The carbonaceous material is at least one carbonaceous material selected from the group consisting of graphite, denka black, ketjen black, acetylene black, carbon nanotubes, carbon nanofibers, carbon nanowires, carbon nanoballs, activated carbon and mixtures thereof Cathode catalyst for phosphorus fuel cells. An anode electrode and a cathode electrode located opposite each other; And A polymer electrolyte membrane positioned between the anode and the cathode electrode, The cathode electrode includes a conductive electrode substrate and a catalyst layer formed on the electrode substrate, 6. The membrane-electrode assembly for a fuel cell, wherein the catalyst layer comprises the cathode catalyst according to any one of claims 1 to 4. The method of claim 5, The polymer electrolyte membrane comprises a polymer resin having at least one cation exchange group selected from the group consisting of sulfonic acid groups, carboxylic acid groups, phosphoric acid groups, phosphonic acid groups, derivatives thereof, and combinations thereof in the side chain. -Electrode assembly. The method of claim 6, The polymer resin may be a fluorine polymer, a benzimidazole polymer, a polyimide polymer, a polyetherimide polymer, a polyphenylene sulfide polymer, a polysulfone polymer, a polyether sulfone polymer, a polyether ketone polymer, a poly Membrane-electrode assembly for fuel cell, which is at least one polymer resin selected from the group consisting of ether-ether ketone polymers, polyphenylquinoxaline polymers, and combinations thereof. The method of claim 7, wherein The polymer resin is tetrafluoroethylene including poly (perfluorosulfonic acid), poly (perfluorocarboxylic acid), sulfonic acid group. Copolymers of fluorovinylethers containing sulfonic acid groups, defluorinated sulfided polyetherketones, aryl ketones, poly (2,2'-m-phenylene) -5,5'-bibenzimidazoles (poly (2, Membrane-electrode assembly for fuel cell, which is at least one polymer resin selected from the group consisting of 2 '-(m-phenylene) -5,5'-bibenzimidazole), poly (2,5-benzimidazole), and combinations thereof . The method of claim 5, The anode electrode is platinum, ruthenium, osmium, platinum-ruthenium alloy, platinum-osmium alloy, platinum-palladium alloy, platinum-M alloy (M is Ga, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and at least one transition metal selected from the group consisting of a combination thereof, and at least one catalyst selected from the group consisting of a combination thereof. The method of claim 9, The catalyst is supported on at least one carrier selected from the group consisting of acetylene black, denka black, activated carbon, ketjen black, graphite, alumina, silica, titania, zirconia, and combinations thereof. . An anode electrode and a cathode electrode located opposite each other; And a polymer electrolyte membrane positioned between the anode and the cathode electrode, wherein the cathode electrode comprises a conductive electrode substrate and a catalyst layer formed on the electrode substrate, wherein the catalyst layer is any one of claims 1 to 4. An electricity generator including a membrane-electrode assembly including the cathode catalyst and a separator positioned on both sides of the membrane-electrode assembly; A fuel supply unit supplying fuel to the electricity generation unit; And A fuel cell system comprising an oxidant supply unit for supplying an oxidant to the electricity generation unit. The method of claim 11, The fuel cell system is selected from the group consisting of a polymer electrolyte fuel cell and a direct oxidation fuel cell. The method of claim 12, And the fuel cell system is a direct oxidation fuel cell.

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