Method for producing a fuel cell catalyst including a porous support with controlled physical properties, a fuel cell catalyst, and a membrane-electrode assembly

Abstract

The present invention relates to a method for producing a fuel cell catalyst including a porous support with adjusted physical properties, a fuel cell catalyst, and a membrane-electrode assembly. More specifically, the present invention relates to a method for producing a fuel cell catalyst, a fuel cell catalyst, and a membrane-electrode assembly, which include a first step of preparing a porous support, and a second step of preparing a fuel cell catalyst by supporting a metal catalyst on the porous support prepared in the first step, wherein the porous support has specific pore properties.

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a catalyst for a fuel cell including a porous support having controlled physical properties, a catalyst for a fuel cell, and a membrane-electrode assembly, and more particularly to a method for manufacturing a catalyst for a fuel cell including a porous support having controlled physical properties using a porous support having controlled porosity, a catalyst for a fuel cell, and a membrane-electrode assembly. [Background technology]

[0002] In recent years, environmental pollution caused by the excessive use of fossil fuels and the sharp rise in oil prices have led to growing interest in fuel cells, which are energy-efficient and produce minimal pollution. Fuel cells convert the chemical energy of raw materials directly into electrical energy using an electrochemical conversion method, rather than converting it into mechanical energy. While fuel cells operate on the opposite principle to water electrolysis, where water is split into hydrogen and oxygen using external electricity, fuel cells generate electricity through an electrochemical reaction between hydrogen and oxygen. This can be expressed as chemical reaction equations (1) and (2).

[0003] Formula (1)

[0004] Anode electrode: H2 → 2H + +2e -

[0005] The reaction at the anode is an oxidation reaction, and the oxidation of hydrogen occurs easily with a platinum catalyst. The anode catalyst of a low-temperature fuel cell must oxidize hydrogen. In actual systems, the fuel may contain CO, S, or NH3 rather than pure hydrogen. Among these, CO is a major toxic substance in low-temperature fuel cells and is easily adsorbed by the platinum catalyst. Carbon monoxide adsorbed on the platinum catalyst weakens the catalyst by attaching to the catalyst's active sites and reducing the reaction area with hydrogen. To reduce the damage caused by carbon monoxide, CO must be oxidized to CO2.

[0006] Formula (2)

[0007] Cathode electrode: 1 / 2O2 + 2H + +2e - →H2O

[0008] The reaction at the cathode is a reduction reaction, which travels through the electrolyte to the anode, where it combines with the hydrogen oxidized at the anode to produce water. The cathode has been extensively studied due to the superiority of platinum-based catalysts, which are the most effective at reducing oxygen. To compensate for the low reactivity associated with low-temperature operation, a high amount of metal is added for the oxygen catalyst. This type of fuel cell also uses air as the cathode gas, but the partial pressure of oxygen is lower than that of pure oxygen, reducing the activity of the reaction. The porosity of the cathode layer can be optimized by adding pore-forming materials.

[0009] Fuel cells come in various types, depending on the fuel or material used, including polymer electrolyte membrane fuel cells (PEMFCs), solid oxide fuel cells (SOFCs), and molten carbonate fuel cells (MCFCs). A fuel cell power generation system consists of a fuel reformer, which converts common hydrogen-containing fuels (such as LPG, LNG, methane, and coal gas methanol) into the hydrogen-rich gas required by the fuel cell; a stack, which uses the hydrogen from the fuel reformer and oxygen from the air to generate direct current (DC), water, and heat as a by-product; and an inverter, which converts the DC power output from the fuel cell into alternating current (AC). The most important part of the stack is the membrane electrode assembly (MEA). The membrane electrode assembly (MEA) is a film-like assembly that converts oxygen and hydrogen into electrical energy through a chemical reaction. Hydrogen and oxygen supplied to the fuel cell release electrons from the anode and cathode, respectively, to become ions, and the released electrons escape to the outside to generate electric current. This reaction occurs in the membrane electrode assembly. The membrane-electrode assembly is composed of an electrolyte membrane, an anode, and a cathode.

[0010] Porous carbon has long been attracting attention as a catalyst support due to its diverse pore structure, stability in acidic and basic environments, low cost, and ease of manufacture and processing. Porous carbon, which exhibits regular pore size and structure, has many advantages as a catalyst support, but further research is needed into adjusting the physical properties of porous carbon to improve fuel cell performance.

[0011] In particular, corrosion and agglomeration of the carbon-based support that occurs during fuel cell operation can reduce the electrochemical surface area (ECSA) of the catalytic metal. Using such an electrode catalyst can result in reduced activity and durability, and improvements are needed to address this issue.

[0012] [Prior art document]

[0013] [Patent documents]

[0014] (Patent Document 1) Korean Patent Registration No. 10-1985064

[0015] (Patent Document 2) Korean Patent Registration No. 10-1238887

[0016] (Patent Document 3) Korean Patent Registration No. 10-1473319

[0017] (Patent Document 4) Korean Patent Registration No. 10-0665689

[0018] [Non-patent literature]

[0019] (Non-Patent Document 1) Ordered mesoporous carbons (OMC) as supports of electrocatalysts for direct methanol fuel cells (DMFC): Effect of carbon precursors of OMC on DMFC performances, Received 9 November 2005; received in revised form 15 February 2006; accepted 5 March 2006 Available online 15 May 2006

[0020] (Non-Patent Document 2) Platinum-supported mesoporous carbon (Pt / CMK-3) as anodic catalyst for direct methanol fuel cell applications: The effect of preparation and deposition methods, Progress in Natural Science: Materials International 2012;22(6):616-623 Summary of the Invention [Problem to be solved by the invention]

[0021] The present invention is intended to solve these problems, and its object is to provide a fuel cell catalyst containing a porous support, in which a porous support having satisfactory physical properties is manufactured, or the physical properties of the porous support are adjusted to a specific range by post-treatment, thereby improving mass transfer, and a method for manufacturing the same. [Means for solving the problem]

[0022] According to one embodiment of the present invention, a method for manufacturing a fuel cell catalyst including a porous support having controlled physical properties includes a first step of preparing a porous support, and a second step of preparing a fuel cell catalyst by supporting a metal catalyst on the porous support of the first step, wherein the unit volume of pores of the porous support having a size of 4 to 8 nm is 0.40 to 1.00 cm. 3 / g, BET specific surface area is 300-700m 2 / g, the proportion (S) of the total BET specific surface area is 50 to 90%, and the unit volume of pores of the porous support that are smaller than 4 nm in size is 0.02 to 0.20 cm 3 / g, BET specific surface area is 10-80m 2 / g, the proportion (S) of the total BET specific surface area is 0 to less than 10%, and the unit volume of pores in the porous support having a size of more than 8 nm is 0.20 to 2.20 cm 3 / g, BET specific surface area is 40-400m 2 / g, and the proportion (S) of the total BET specific surface area is 10 to 40%.

[0023] In this case, the physical properties of the porous carrier in the first step may be adjusted by any one or a combination of two or more methods selected from the group consisting of physical particle size adjustment using a bead mill or ultrasound, acid treatment, heat treatment, and activation treatment.

[0024] The porous support in the first step may be any one or a mixture of two or more of a carbonaceous support, a metal oxide, a metal nitride, and a metal carbide.

[0025] A fuel cell catalyst according to one embodiment of the present invention is a catalyst for a fuel cell comprising a porous support and a metal catalyst, and the unit volume of pores of the porous support having a size of 4 to 8 nm is 0.40 to 1.00 cm 3 / g, the BET specific surface area is 300 to 700 m 2 / g, the proportion (S) of the total surface area is 50 to 90%, and the unit volume of pores of the porous support that are less than 4 nm in size is 0.02 to 0.20 cm 3 / g, BET specific surface area is 10-80m 2 / g, the proportion (S) of the total surface area is 0 to less than 10%, and the unit volume of pores in the porous support having a size of more than 8 nm is 0.20 to 2.20 cm 3 / g, BET specific surface area is 40-400m 2 / g, and the proportion (S) of the total surface area is 10 to 40%.

[0026] The porous support may have a main peak (2θ) of 0.8 to 3° in a low-angle XRD pattern.

[0027] The crystal grain size (L C 002) can be 2.0 to 4.5 nm.

[0028] The porous support is a carbon-based support, and the tap density of the carbon is 0.10 to 0.5 g / cm 3 and the G / D ratio of carbon can be 0.7 to 1.3.

[0029] The metal catalyst is dispersed and supported on the porous support, and the amount of the supported metal catalyst may be 10 to 80 wt % based on the total weight of the catalyst.

[0030] The metal catalyst may be any one or a mixture of two or more selected from Pt, PtRu, PtIr, PtCo, PtNi, PtY, PtCoN, and PtCoMn.

[0031] The porous support may have a bimodal or trimodal shape with a single type of pore or with different types of pores.

[0032] A membrane-electrode assembly according to one embodiment of the present invention includes the above-described fuel cell catalyst of the present invention. [Effects of the Invention]

[0033] As described above, the present invention has the effect of improving performance by improving mass transfer and catalyst utilization rate through the control of the porosity of the porous support.

[0034] Furthermore, the present invention has the effect of improving the catalyst distribution by adjusting the porosity of the porous support, thereby improving the durability of the catalyst. [Brief explanation of the drawings]

[0035] [Figure 1] 1 is a flowchart of a method for manufacturing a fuel cell catalyst including a porous support with controlled physical properties according to an embodiment of the present invention.

[0036] [Figure 2] 1 shows the results of fuel cell performance evaluation of catalysts manufactured using carriers according to examples of the present invention and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0037] In the drawings shown below, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience of description. The embodiments described below are merely exemplary, and various modifications are possible from such embodiments. Hereinafter, terms are used only to distinguish one component from another. A singular expression includes a plural expression unless the context clearly indicates otherwise. Furthermore, when a part is said to "comprise" a certain component, this does not mean that it excludes other components, but that it may further include other components, unless otherwise specified.

[0038] In this specification, the "physical property" of the porous support may be any one or more selected from the unit volume of pores, BET specific surface area, main peak (2θ) of a low-angle XRD pattern, crystal grain size (LC002), tap density of carbon, G / D ratio, etc. For each physical property of the porous support adjusted by the present invention, please refer to the contents described in each embodiment of the present invention.

[0039] The method for manufacturing a fuel cell catalyst including a porous support having controlled physical properties of the present invention will be described in detail below. Figure 1 is a flowchart of a method for manufacturing a fuel cell catalyst including a porous support having controlled physical properties of the present invention. Referring to Figure 1, the method for manufacturing a fuel cell catalyst including a porous support having controlled physical properties of the present invention includes the following steps:

[0040] First step (S10): preparing a porous carrier

[0041] Second step (S20): A step of supporting a metal catalyst on the porous support of the first step (S10) to produce a catalyst for a fuel cell.

[0042] Here, the unit volume of pores of the porous support having a size of 4 to 8 nm is 0.40 to 1.00 cm 3 / g, BET specific surface area is 300-700m 2 / g, the ratio (S) of the total surface area is 50 to 90%, and the unit volume of pores of the porous support that are less than 4 nm in size is 0.02 to 0.20 cm 3 / g, BET specific surface area is 10-80m 2 / g, the proportion (S) of the total surface area is 0 to less than 10%, and the unit volume of pores in the porous support having a size of more than 8 nm is 0.20 to 2.20 cm 3 / g, BET specific surface area is 40-400m 2 / g, and the proportion (S) of the total surface area is 10 to 40%.

[0043] The porous support of the present invention preferably satisfies all of the above-mentioned conditions, and the unit volume of the pores can be calculated by the BJH calculation method after adjusting to the range of the pores after BET measurement.

[0044] Generally, porous carriers are classified into micropores, mesopores, and macropores depending on the pore diameter. Here, micropores refer to pores with an average diameter of 2 nm or less, particularly 0.01 to 2 nm, mesopores refer to pores with an average diameter of more than 2 nm but not more than 50 nm, and macropores refer to pores with an average diameter of more than 50 nm, particularly more than 50 nm but not more than 500 nm. Therefore, the porous carrier with adjusted physical properties of the present invention uses mesopores, and it is preferable to use mesopores with a pore size of 4 to 8 nm.

[0045] The proportion of pores with a pore size of 4 to 8 nm in the total surface area of ​​the porous support of the present invention is preferably 50 to 90%. In this case, the proportion of pores is obtained by dividing the surface area of ​​the porous support by the total surface area. When the above proportion is satisfied, the majority of pores are mesopores, and the more mesopores there are, the more advantageous the properties are in terms of improving fuel cell performance.

[0046] According to the present invention, the porous carrier having adjusted physical properties has a total specific surface area (BET) of 100 to 1,000 m 2 / g. Preferably, the specific surface area (BET) of the porous carrier with adjusted physical properties is 200 to 800 m 2 / g, the specific surface area of ​​the porous carrier may be in the range of 200 m 2 If the specific surface area of ​​the porous carrier is less than 800 m / g, it is difficult to achieve high dispersion of the active metal. 2 If it exceeds 1 / g, the proportion of mesopores will decrease and the proportion of micropores will increase, which may be a problem, so the above range is appropriate.

[0047] Furthermore, the pores of the porous carrier having controlled physical properties of the present invention may be bimodal or trimodal in shape having a single type of pore or more than one type of pore.

[0048] The first step (S10) is a step of preparing a porous support. The porous support of the present invention can be one or a mixture of two or more of a carbon-based support, a metal oxide, a metal nitride, and a metal carbide.

[0049] The carbon-based support of the present invention may be at least one selected from the group consisting of, but not limited to, activated carbon, carbon black, graphite, graphene, ordered mesoporous carbon (OMC), and carbon nanotubes. Preferably, the carbon black has a high mesopore ratio. Specific examples of the activated carbon include SX ULTRA, CGSP, PK1-3, SX 1G, DRACO S51HF, CA-1, A-51, GAS 1240 PLUS, KBG, CASP, and SX PLUS. Examples of the carbon black include, but are not limited to, BLACK PEARLS, ELFTEX, VULCAN, MOGU, MONARCH, EMPEROR, and REGAL.

[0050] The porous carrier in the first step (S10) may be prepared by, but is not limited to, a hard or soft template replication method, in which a precursor is placed in a template, a porous carrier is prepared by appropriate treatment, and then the template is removed. The porous carrier prepared by such a method may be a mesoporous carrier.

[0051] Specifically, the hard template method is a method in which a precursor is injected into a hard template such as mesoporous silica, and the precursor is oxidized, reduced, polymerized, or carbonized to produce a replicated shape, and then the template is removed to produce a final product. The soft template method is a method in which a precursor is oxidized, reduced, polymerized, or carbonized using a template that has a specific shape but is not hard, such as a surfactant, to produce a replicated shape, and then the template is removed to produce a final product.

[0052] The metal oxide of the present invention may be one or a mixture of two or more selected from yttrium oxide (YO), aluminum oxide (AlO), magnesium oxide (MgO), zinc oxide (ZnO), tin oxide (SnO), indium oxide (InO), iron oxide (FeO), titanium oxide (TiO), zirconium oxide (ZrO), chromium oxide (CrO), hafnium oxide (HfO), and berinium oxide (BeO).

[0053] The metal nitride of the present invention can be one or a mixture of two or more selected from niobium nitride, tin nitride, indium nitride, platinum nitride, tantalum nitride, zirconium nitride, copper nitride, iron nitride, tungsten nitride, chromium nitride, molybdenum nitride, hafnium nitride, titanium nitride, vanadium nitride, cobalt nitride, manganese nitride, cerium nitride, mercury nitride, plutonium nitride, gold nitride, silver nitride, iridium nitride, palladium nitride, yttrium nitride, ruthenium nitride, lanthanum nitride, cerium nitride, praseodymium nitride, neodymium nitride, promethium nitride, samarium nitride, europium nitride, gadolinium nitride, terbium nitride, dysprosium nitride, holmium nitride, erbium nitride, thulium nitride, ytterbium nitride, lutetium nitride, and nickel nitride.

[0054] As the metal carbide of the present invention, one or a mixture of two or more selected from SiC, B4C, TiC, CrC, MoC, WC, NbC and NiC can be used.

[0055] Meanwhile, the first step may include a step of adjusting the physical properties of the porous support. The adjustment of the physical properties may be performed by, for example, adjusting the physical particle size using a bead mill or ultrasound, or by any one or a combination of two or more methods selected from the group consisting of acid treatment, heat treatment, and activation treatment. The acid treatment, heat treatment, activation treatment, etc. may be performed by methods known in the art. A treatment method may be selected and used depending on the desired physical properties, and various methods may be combined as necessary to adjust the physical properties. For example, the pores are basically formed by removing the portion used as a template, and are further generated when carbon is subjected to a heat treatment such as graphitization or an activation treatment using water vapor or carbon dioxide. The physical properties of the porous support can be adjusted by appropriately adjusting the conditions of these treatments.

[0056] The porous carrier having controlled physical properties of the present invention may be subjected to a separate acid treatment. For example, the post-treatment may be performed with a nitric acid (HNO3) aqueous solution, which may contain 1 to 50 parts by weight of nitric acid per 100 parts by weight of the total aqueous solution. The post-treatment may be performed at a temperature of 50 to 150°C for 1 to 10 hours.

[0057] Meanwhile, the porous support may have a main peak (2θ) of 0.8 to 3° in the low-angle XRD pattern. Measurement of the main peak (2θ) of the low-angle XRD pattern is the same as that of XRD analysis, but only from 2θ values ​​of 0.1 to 10°. This is useful for analyzing the mesoporous structure material of the porous support of the present invention. If the main peak (2θ) value is less than 0.8°, the size of the main pores tends to increase, failing to satisfy the intended physical properties of the present invention. On the other hand, if the main peak (2θ) value is greater than 3°, the size of the main pores tends to decrease, similar to the size of the micropores, failing to satisfy the intended physical properties of the present invention.

[0058] In addition, the crystal grain size (L C The crystalline grain size (002) is preferably 2.0 to 4.5 nm. Here, the crystalline grain size can be calculated by the Scherrer equation for the peak of the 002 plane of carbon after XRD analysis. If the crystalline grain size of the porous support is less than 2.0 nm, the durability of the support may be reduced. If the crystalline grain size of the porous support is more than 4.5 nm, the hard surface of the support makes it difficult to uniformly support the metal catalyst, and it is difficult for the metal catalyst to bond to the support, which may reduce catalyst durability.

[0059] The porous carrier of the present invention can be a carbon-based carrier, a metal oxide, a metal nitride, or a metal carbide, but a carbon-based carrier is mainly used. When a carbon-based carrier is used as the porous carrier, in addition to the above physical properties, the tap density of the carbon is 0.10 to 0.5 g / cm. 3 , and more preferably 0.12 to 0.48 g / cm 3 The G / D ratio may be 0.7 to 1.3, more preferably 0.8 to 1.28. The tap density of the porous support, i.e., carbon, is 0.10 g / cm 3 If the concentration is less than 0.5 g / cm, the carrier floats in the solvent, reducing dispersibility. 3If the thickness exceeds this value, the dispersibility due to the cohesive force between the carriers may decrease, making it difficult to uniformly support the metal catalyst.

[0060] Furthermore, if the G / D ratio of the porous support, i.e., carbon, is less than 0.7, the durability of the support will decrease, and if it exceeds 1.3, it will be difficult for the catalyst to be uniformly supported on the hard support surface, making it difficult for the catalyst to bond to the support, which may result in a decrease in catalyst durability.

[0061] The second step (S20) is a step of preparing a fuel cell catalyst by supporting a metal catalyst on the porous support of the first step (S10). The metal catalyst used in the present invention may be one or a mixture of two or more selected from Pt, PtRu, PtIr, PtCo, PtNi, PtY, PtCoNi, and PtCoMn.

[0062] The amount of the metal catalyst supported in the second step is preferably 10 to 80 wt %. If the metal catalyst content is less than the above range, the electrode layer will relatively increase in thickness, resulting in reduced performance. If the metal catalyst content is greater than the above range, it is economically disadvantageous and the catalyst particle size may increase. In consideration of these points, the metal catalyst content in the supported catalyst is preferably 10 to 80 wt %. The amount of the metal catalyst supported in the present invention can be determined by TGA analysis.

[0063] The present invention provides a method for manufacturing a membrane electrode assembly using a fuel cell catalyst layer obtained by the method for manufacturing a fuel cell catalyst, which includes the porous support having the adjusted physical properties. The membrane electrode assembly (MEM) of the present invention may include a proton exchange membrane, a fuel cell catalyst layer, and a gas diffusion layer (GDL). When a membrane electrode assembly is manufactured using the porous support having the adjusted physical properties provided in the fuel cell catalyst layer, the porosity of the porous support is optimally adjusted, thereby improving mass transfer and catalyst utilization. [Example]

[0064] Example 1

[0065] Five grams of a carbon precursor (phenolic resin) was injected into 10 grams of a template (ordered mesoporous silica, pore size approximately 15 nm) by vapor adsorption at 120°C for one hour, followed by polymerization at 160°C for two hours. The physical particle size of the resulting silica-polymer composite was adjusted using ultrasound, and excess polymer was removed. The composite was then carbonized at 1,000°C for six hours under an Ar atmosphere. This was followed by graphitization at 2,000°C for two hours and wet etching using NaOH or KOH to produce a porous graphitized carbon support with the physical properties listed in Table 1 below.

[0066] Example 2

[0067] The porous graphitized carbon support prepared in Example 1 was post-treated with steam at 400°C for 2 hours to prepare a post-treated porous graphitized carbon support having the physical properties shown in Table 1 below.

[0068] (Comparative Example 1)

[0069] Commercial Vulcan XC-72 Carbon

[0070] (Comparative Example 2)

[0071] The carbon precursor was filled into the pores of a conventional SBA-15 silica template (pore size 7.5 nm) to a volume 1.1 to 1.7 times the size of the template, heat-treated at 1,000°C under Ar conditions, and then the template was removed to produce mesoporous carbon (CMK-3).

[0072] (Comparative Example 3)

[0073] The pores of standard SBA-15 silica (pore size 7.5 nm) were filled with a carbon precursor 1.1 to 1.7 times the amount of the template, carbonized at 1,000°C for 6 hours under Ar conditions, and then graphitized at 2,000°C for 2 hours. The template was then removed to produce a porous graphitized carbon support. The produced porous graphitized carbon support was then pulverized in a bead mill for 30 minutes to produce a post-treated porous graphitized carbon support.

[0074] (Physical properties of carbon supports)

[0075] [Table 1]

[0076] The Examples satisfied all the physical properties required by the present invention, but Comparative Example 1 was inadequate in terms of physical properties in terms of <4 nm pore volume, 4-8 nm pore volume, total BET specific surface area and ratio, and Comparative Example 2 was inadequate in terms of physical properties in terms of <4 nm BET specific surface area and ratio, Lc002 crystallite size, tapped density, and G / D ratio. Comparative Example 3 was inadequate in terms of physical properties in terms of BET specific surface area of ​​pores sized 4-8 nm, and unit volume and BET specific surface area of ​​pores sized over 8 nm. Example 1 exhibited improved catalyst distribution and improved catalyst durability compared to Comparative Examples 1-3.

[0077] (Manufacturing example)

[0078] Catalysts carrying 50% Pt were prepared using the carbons of the Examples and Comparative Examples by polyol reduction method.

[0079] (Evaluation example) Battery performance evaluation: Evaluation results under conditions of 80°C and 50 RH

[0080] A fuel cell was fabricated using the catalyst of Preparation Example 1, and the cell performance was evaluated, and the results are shown in Figure 2. From Figure 2, it can be seen that the catalyst prepared using the carrier with controlled physical properties of the Example according to the present invention exhibits superior performance compared to the catalyst of the Comparative Example.

[0081] The present invention is not limited to the above-described embodiments, and can be manufactured in various forms. Those skilled in the art will understand that the present invention can be embodied in other specific forms without changing the technical concept or essential characteristics of the present invention. Therefore, the above-described embodiments should be understood to be illustrative in all respects and not limiting.

Claims

1. A first step of providing a porous carrier; a second step of supporting a metal catalyst on the porous support of the first step to produce a catalyst for a fuel cell; Among the pores in the porous carrier, the unit volume of pores with a size of 4 to 8 nm is 0.40 to 1.00 cm ３ / g, BET specific surface area is 300-700m ２ / g, the proportion (S) of the total BET specific surface area is 50 to 90%, and the unit volume of pores of the porous support having a size of less than 4 nm is 0.02 to 0.20 cm ３ / g, BET specific surface area is 10 to 80 m ２ / g, the ratio (S) of the total BET specific surface area is 0 to less than 10%, and the unit volume of pores of the porous support having a size exceeding 8 nm is 0.20 to 2.20 cm ３ / g, BET specific surface area is 40 to 400 m ２ / g, and the ratio (S) of the total BET specific surface area is 10 to 40%.

2. 2. The method for producing a fuel cell catalyst according to claim 1, wherein the physical properties of the porous support in the first step are adjusted by one or a combination of two or more methods selected from the group consisting of physical particle size adjustment using a bead mill or ultrasound, acid treatment, heat treatment, and activation treatment.

3. 2. The method for producing a catalyst for a fuel cell according to claim 1, wherein the porous support in the first step is any one or a mixture of two or more of a carbon-based support, a metal oxide, a metal nitride, and a metal carbide.

4. A catalyst for a fuel cell comprising a porous support and a metal catalyst, Among the pores in the porous carrier, the unit volume of pores with a size of 4 to 8 nm is 0.40 to 1.00 cm ３ / g, BET specific surface area is 300-700m ２ / g, the proportion (S) of the total BET specific surface area is 50 to 90%, The unit volume of the pores in the porous carrier that are less than 4 nm in size is 0.02 to 0.20 cm ３ / g, BET specific surface area is 10 to 80 m ２ / g, the proportion (S) of the total BET specific surface area is 0 to less than 10%; The unit volume of the pores of the porous carrier having a size exceeding 8 nm is 0.20 to 2.20 cm ３ / g, BET specific surface area is 40 to 400 m ２ / g, and the proportion (S) of the total BET specific surface area is 10 to 40%.

5. 5. The fuel cell catalyst according to claim 4, wherein the porous support has a main peak (2θ) of 0.8 to 3° in a low angle XRD pattern.

6. The crystal grain size (L Ｃ 5. The fuel cell catalyst according to claim 4, wherein 002) is 2.0 to 4.5 nm.

7. The porous support is a carbon-based support, and the tap density of the carbon is 0.10 to 0.5 g / cm ３ 5. The fuel cell catalyst according to claim 4, wherein the G / D ratio of the carbon is 0.7 to 1.

3.

8. 5. The fuel cell catalyst according to claim 4, wherein the metal catalyst is dispersed and supported on the porous support, and the amount of the supported metal catalyst is 10 to 80% by weight based on the total weight of the catalyst.

9. 5. The fuel cell catalyst according to claim 4, wherein the metal catalyst is one or a mixture of two or more selected from the group consisting of Pt, PtRu, PtIr, PtCo, PtNi, PtY, PtCoN, and PtCoMn.

10. 5. The fuel cell catalyst according to claim 4, wherein the porous support has a bimodal or trimodal shape with a single type of pore or different types of pores.

11. A membrane-electrode assembly comprising the fuel cell catalyst according to any one of claims 4 to 10.

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