JP2006164574A - Water-repellent electrode catalyst layer for solid polymer fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-repellent electrode catalyst layer for a solid polymer fuel cell and a manufacturing method thereof, and a fuel cell having the water-repellent electrode catalyst layer. <P>SOLUTION: A water-repellent electrode catalyst layer for a solid polymer fuel cell is provided, wherein: (1) the electrode catalyst layer contains a solid polymer electrolyte, a catalyst material and a water-repellent carbon material; (2) the catalyst material is formed of a catalyst active component supported by the carbon material; and (3) the water-repellent carbon material is formed by adding a water-repellent material to a part of the surface of the carbon material by a vapor phase method. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to an electrode catalyst layer for a polymer electrolyte fuel cell.

  Conventionally, fuel cells have been mainly used in the fields of space development and marine development. In recent years, expectations for fuel cells have increased rapidly from the viewpoint of protecting the global environment and from the viewpoint of high energy conversion efficiency when hydrogen is used directly as a fuel. Then, instead of an automobile engine, it has been developed into a home power generator, and the possibility of being widely used is increasing.

  A fuel cell simply refers to a device that continuously supplies fuel (reducing agent) and oxygen or air (oxidant) from the outside and reacts them electrochemically to extract electrical energy.

  The classification of the fuel cell is performed on the basis of the operating temperature, the type of fuel used, the application, and the like, and is mainly performed on the basis of the type of electrolyte used. Specifically, the types of electrolytes are classified into solid oxide fuel cells (SOFC), molten carbonate fuel cells (MCFC), phosphoric acid fuel cells (PAFC), and polymer electrolyte fuel cells (PEFC: Polymer Electrolyte Fuel Cell) and alkaline aqueous fuel cell (AFC). These five types use hydrogen gas generated from methane or the like as fuel. Furthermore, a direct methanol fuel cell (DMFC) that directly uses an aqueous methanol solution as a fuel is also known.

  Among such fuel cells, in particular, a polymer electrolyte fuel cell having a structure in which a solid polymer membrane is sandwiched between two types of electrodes and these members are sandwiched between separators has attracted attention. In this polymer electrolyte fuel cell, an electrode such as an air electrode (oxygen electrode) and a fuel electrode (hydrogen electrode) is usually arranged on both sides of a solid polymer membrane to constitute a unit cell. Both sides are sandwiched between fuel cell separators. In other words, a fuel electrode and an air electrode made of a catalyst layer are formed on both sides of the solid polymer film and integrated, and a porous support layer (carbon paper) is attached to the outside of the catalyst layer as a current collector, and hydrogen, oxygen, etc. It is clamped by a separator (partition plate) that also serves as a reaction gas supply path. In this polymer electrolyte fuel cell, it is necessary to isolate the fuel (hydrogen) and oxidant (air) from each other and to transport hydrogen ions (protons) generated at the fuel electrode to the air electrode side. is there.

  One of the required functions of the electrode catalyst layer is that the generated water generated in the power generation process is quickly discharged from the catalyst layer to ensure the flow path of the fuel gas and oxidant gas.

  Fuel gas and oxidant gas are supplied while being humidified according to the operating conditions. For this reason, if humidification increases too much, dew condensation due to water vapor occurs in the electrode catalyst layer. When the amount of water droplets increases, there arises a problem that the water droplets block the voids in the electrode catalyst layer and the gas supply decreases.

  The rapid discharge of generated water and condensed water depends on the wettability of the electrode catalyst layer with respect to water, and greatly affects the performance of the fuel cell (cell maximum output density, resistance value, etc.). For this reason, various efforts have been made to provide the characteristic of quickly discharging generated water and condensed water from the electrode catalyst layer.

For example, there is a method of using a porous material made of carbon paper or carbon fiber as an electrode and forming a layer in which a conductive material such as carbon black or graphite and a fluororesin that is a binder and water repellent material are mixed. (Patent Document 1, Patent Document 2)
Also, a water repellent treatment method of mixing a conductive material such as carbon black and carbon paper with a silane coupling agent in the presence of ethanol, and a water repellent treatment method of mixing with a silane coupling agent while being dispersed in a cyclic silicone oil Is provided (Patent Document 3).

  However, in the former case, if the amount of the water repellent is large, the electrical resistance value increases, so that sufficient conductivity cannot be maintained. Conversely, if the water repellent material is small, sufficient water repellency cannot be obtained and gas permeation is hindered. As a result, there arises a problem that the battery performance is lowered.

In the latter case, since the carbonaceous material such as carbon black is dispersed in alcohol or liquid silicone, the entire carbonaceous material is covered with a resistor. The water-repellent substance is limited to a specific substance such as a silane coupling agent that easily reacts with a functional group on the surface of the carbonaceous material.
JP-A-10-261421 JP 2001-43865 A JP 2000-239704 A

  Thus, although development of a technique for efficiently discharging generated water and the like without impairing battery characteristics is desired, it has not yet been developed.

  Accordingly, the present invention has been made in view of these problems of the prior art, and in particular, to provide an electrode catalyst layer of a polymer electrolyte fuel cell having excellent water repellency without impairing battery characteristics. With a purpose.

  In light of the problems of the prior art described above, the present inventor has found that the object can be achieved by using an electrode catalyst layer having a specific configuration, and has completed the present invention.

That is, the present invention relates to a water-repellent electrode catalyst layer, a production method thereof, and a fuel cell including the water-repellent electrode catalyst layer described below.
1. An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte, a catalyst material, and a water-repellent carbon material,
2) The catalyst material comprises a carbon material carrying a catalytically active component,
3) The water-repellent carbon material is formed by imparting a water-repellent material to a part of the surface of the carbon material by a vapor phase method.
A water-repellent electrode catalyst layer characterized by the above.
2. An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte and a water-repellent catalyst material,
2) The water-repellent catalyst material is formed by applying a water-repellent material to a part of the surface of a catalyst material obtained by supporting a catalytic active component on a carbon material by a gas phase method.
A water-repellent electrode catalyst layer characterized by the above.
3. An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte, a water repellent carbon material, and a water repellent catalyst material,
2) The water-repellent carbon material is formed by imparting a water-repellent material to a part of the surface of the carbon material,
3) The water-repellent catalyst material is formed by imparting a water-repellent material to a part of the surface of the catalyst material obtained by supporting a catalytically active component on a carbon material,
4) The application of the water-repellent material in 2) and / or 3) is performed by a vapor phase method.
A water-repellent electrode catalyst layer characterized by the above.
4). Item 4. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of Items 1 to 3, wherein the vapor phase method is a chemical vapor deposition method.
5. Item 5. The solid polymer form according to any one of Items 1 to 4, wherein the water-repellent material is at least one of 1) an organometallic compound having a carbon-containing group, 2) a hydrocarbon compound, and 3) a fluorine-containing compound. Water repellent electrode catalyst layer for fuel cells.
6). An organometallic compound having a carbon-containing group is represented by Si _x O _y C _z Hα (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ z ≦ 50, 1 ≦ α ≦ 122). Item 6. The water repellent electrode catalyst layer for a polymer electrolyte fuel cell according to Item 5, which is an organic silicon material and / or a polymer thereof.
7). The fluorine-containing compound is 1) Si _x O _y C _z HαFβ (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ z ≦ 50, 1 ≦ α ≦ 122, 1 ≦ β ≦ 122) 2) Si _x O _y HαFβ (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 0 ≦ α ≦ 21, 1 ≦ β ≦ 22) 3) C _x O _y H _z Fα (where 1 ≦ x ≦ 50, 0 ≦ y ≦ 10, 0 ≦ z ≦ 102, 0 ≦) 6. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to Item 5, which is at least one of a fluorine-containing hydrocarbon-based material and / or a polymer thereof represented by α ≦ 102.
8). Item 5. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of Items 1 to 4, wherein the water-repellent material is a self-assembled monomolecular film.
9. The self-assembled monolayer has the following general formula (1):
R ¹ XR ² (1)
(Where R ¹ represents an alkyl group or an aryl group. R ² represents hydrogen, halogen, or —OR ³ (R ³ represents an alkyl group, an allyl group, or an aryl group). X represents Si, Ti, Al, C or S.)
Item 9. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to Item 8, which is formed of the compound represented by
10. 10. The water repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of Items 1 to 9, wherein the water repellent material has a contact angle with water of 70 to 170 °.
11. 11. A polymer polymer fuel cell catalyst layer-electrolyte membrane assembly, wherein the water-repellent electrode catalyst layer according to any one of Items 1 to 10 is joined to an electrolyte membrane.
12 A unit cell for a polymer electrolyte fuel cell, comprising the catalyst layer-electrolyte membrane assembly according to Item 11.
13. 13. A polymer electrolyte fuel cell comprising the unit cell according to item 12.
14 A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of applying a water repellent material to a part of a carbon material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte, a catalyst material, and a water-repellent carbon material,
2) The catalyst material comprises a carbon material carrying a catalytically active component,
3) The water-repellent carbon material has a water-repellent material on a part of the surface of the carbon material.
A method for producing a water-repellent electrode catalyst layer.
15. A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of applying a water-repellent material to a part of the catalyst material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte and a water-repellent catalyst material,
2) The water-repellent catalyst material has a water-repellent material on a part of the surface of the catalyst material formed by supporting a catalytically active component on a carbon material.
A method for producing a water-repellent electrode catalyst layer.
16. A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of imparting a water-repellent material to a part of a carbon material and / or catalyst material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte, a water repellent carbon material, and a water repellent catalyst material,
2) The water-repellent carbon material has a water-repellent material on a part of the surface of the carbon material,
3) The water-repellent catalyst material has a water-repellent material on a part of the surface of the catalyst material in which a catalytically active component is supported on a carbon material.
A method for producing a water-repellent electrode catalyst layer.
17. Item 17. The method for producing a water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of Items 14 to 16, wherein the vapor phase method is a chemical vapor deposition method.
18. Item 18. The method for producing a water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to Item 17, wherein the chemical vapor deposition method is plasma CVD.
19. Item 18. The method for producing a water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to Item 17, wherein the chemical vapor deposition method is thermal CVD.

  According to the present invention, in order to form a specific structure in the electrode catalyst layer, that is, the catalyst layer has high water repellency, moisture generated during the battery reaction is diffused to prevent residual, It is possible to prevent clogging of the gap. Therefore, water generated by the reaction of the fuel cell can be discharged smoothly, and at the same time, the fuel gas can be supplied smoothly.

Furthermore, since the water repellent material is formed on the surface of the carbon material in the catalyst layer to such an extent that the conductivity is not lost by the vapor phase method, the passage of electrons is not obstructed, and the electrode catalyst layer of the present invention has conductivity. High water repellency can be obtained in the maintained state.
As a result, the fuel cell having the electrode catalyst layer of the present invention can prevent a decrease in the supply of fuel gas caused by long-time operation, and at the same time maintain high conductivity. Therefore, it is possible to prevent deterioration of the battery, supply a high maximum output density, and reduce the resistance value of the battery.

The water-repellent electrode catalyst layer of the present invention is
(1) An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte, a catalyst material, and a water-repellent carbon material,
2) The catalyst material comprises a carbon material carrying a catalytically active component,
3) The water-repellent carbon material is formed by imparting a water-repellent material to a part of the surface of the carbon material by a vapor phase method.
It is characterized by
(2) An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte and a water-repellent catalyst material,
2) The water-repellent catalyst material is formed by applying a water-repellent material to a part of the surface of a catalyst material obtained by supporting a catalytic active component on a carbon material by a gas phase method.
Or (3) an electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte, a water repellent carbon material, and a water repellent catalyst material,
2) The water-repellent carbon material is formed by imparting a water-repellent material to a part of the surface of the carbon material,
3) The water-repellent catalyst material is formed by imparting a water-repellent material to a part of the surface of the catalyst material obtained by supporting a catalytically active component on a carbon material,
4) The application of the water-repellent material in 2) and / or 3) is performed by a vapor phase method.
It is characterized by that.
(Solid polymer electrolyte)
The solid polymer electrolyte of the present invention is not particularly limited as long as it has hydrogen ion conductivity, and a known one can be used. Examples thereof include perfluorosulfonic acid-based fluorine ion exchange resins; hydrocarbon resins into which phosphoric acid groups, sulfonic acid groups and the like are introduced. Among these, perfluorosulfonic acid-based fluorine ion exchange resins are preferable.
(Carbon material)
The carbon material used in the present invention is not particularly limited, and known materials can be used. For example, channel black, furnace black, ketjen black, acetylene black, lamp black and other carbon black, graphite, activated carbon, carbon fiber, carbon nanotube, etc. can be used alone or in combination.

  The structure, surface shape and the like of the carbon material are not particularly limited, and can be appropriately determined according to the purpose.

  The shape of the carbonaceous material is not particularly limited, and examples thereof include a bead shape, a pellet shape, a powder shape, and a flake shape, and a powder shape is particularly preferable.

  The particle size of the carbon material is about 1 to 200 nm, preferably 10 nm to 100 nm, more preferably about 10 nm to 50 nm as primary particles.

Usually 10m ² / g~2000m ² / g as a specific surface area of the carbon material, preferably 200m ² / g~1500m ² / g.
(Catalyst material)
The catalyst material is one in which the following catalytically active components are supported on the carbon material.

  The catalyst active component to be supported is not particularly limited as long as it causes a reaction at the fuel electrode or air electrode of the fuel cell. For example, platinum, a platinum compound, etc. are mentioned. Examples of the platinum compound include an alloy of platinum and at least one metal selected from the group consisting of ruthenium, palladium, nickel, molybdenum, iridium, iron and the like.

  The particle size of the catalytically active component is usually about 1 nm to 20 nm, preferably about 1 nm to 10 nm, and more preferably about 1 nm to 5 nm.

Usually 50m ² / g~1000m ² / g as specific surface area of the catalytically active component, preferably 100m ² / g~500m ² / g.
(Water repellent material)
The substance constituting the water repellent material is not particularly limited as long as it is a substance having water repellency. For example, organometallic compounds having a carbon-containing group; hydrocarbon compounds; fluorine-containing compounds; nitrogen-containing compounds. Among these, from the viewpoint of having high water repellency, an organometallic compound having a carbon-containing group; a hydrocarbon compound; and a fluorine-containing compound are preferable.

Hereinafter, the organometallic compound having a carbon-containing group, the hydrocarbon compound, and the fluorine-containing compound will be described.
(1) Organometallic compound having a carbon-containing group The organometallic compound having a carbon-containing group is not particularly limited as long as it has at least one metal-carbon bond in the molecule.

  The central metal is not particularly limited, and examples thereof include Si, Ti, Al, Zn, Cu, Ni, Co, Fe, and combinations thereof. Among these, at least one of Si, Ti, and Al is preferable.

  The number of carbon atoms in the carbon-containing group is not particularly limited. In the present invention, those having 1 to 30 carbon atoms are preferable, among which 1 to 6 carbon atoms are more preferable, and particularly, a methyl group having 1 carbon atom or an ethyl group having 2 carbon atoms is most preferable.

Preferable specific examples include an organic silicon-based material represented by Si _x O _y C _z Hα (1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ _z ≦ 50, 1 ≦ α ≦ 122) or a polymer thereof. Is mentioned.

More specifically, hexamethyldisiloxane (HMDSO; (CH ₃ ) ₃ SiOSi (CH ₃ ) ₃ ), tetramethyldisiloxane (TMDSO; (CH ₃ ) ₂ HSiOSiH (CH ₃ ) ₂ ), tetramethylsilane ( TMS; Si (CH ₃ ) ₄ ) and the like.
(2) Hydrocarbon compound The hydrocarbon compound is not particularly limited as long as it is composed of C and H, and examples thereof include a hydrocarbon-based material or a polymer thereof.

Specific examples include polyolefin materials such as polyethylene resins and cyclic polyolefin resins and / or polymers thereof, C ₂ H ₂ , C ₂ H ₄ , CH ₄ , C ₂ H _{6 and the} like.
(3) Fluorine-containing compound The fluorine-containing compound is not particularly limited as long as it contains fluorine. For example, an organic film represented by Si _x O _y C _z HαFβ (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ z ≦ 50, 1 ≦ α ≦ 122, 1 ≦ β ≦ 122) is shown. Silicon fluoride material or polymer thereof; Si _x O _y HαFβ (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ α ≦ 21, 1 ≦ β ≦ 22) Fluorine-containing hydrocarbon represented by C _x O _y H _z Fα (where 1 ≦ x ≦ 50, 0 ≦ y ≦ 10, 0 ≦ z ≦ 102, 0 ≦ α ≦ 102) Examples thereof include fluorine-containing carbon-hydrogen materials and polymers thereof represented by C _x F _y (where 1 ≦ x ≦ 50, 0 ≦ y ≦ 10). Among these, Si _x O represented by _{Si x O y HαFβ; y C} z organic fluoride represented by Harufaefubeta silicon material or a polymer Kka silicon material or a polymer thereof; C _x O _y H _z fluorine-containing hydrocarbon represented by Fα material or a polymer thereof are preferable.

Specific examples include PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoroethylene), PVF (polyvinyl fluoride), ETFE (ethylene / tetrafluoroethylene copolymer), CF ₄ , C ₂ F ₂ , C ₂ F ₄ , C ₂ F _{6 and the} like can be mentioned.

  Here, when the water repellent layer is a silicon oxide layer containing oxygen atoms and silicon atoms, the concentration of oxygen atoms in the water repellent layer is not particularly limited, but there is an upper limit for the number of Si atoms of 100. Preferably it is about 50, more preferably about 25.

  Since oxygen atoms easily form hydrogen bonds with water molecules, having oxygen atoms in the water-repellent material causes the water molecules to be attracted, resulting in a decrease in water repellency. In the water repellent material, since the concentration of oxygen atoms is within the above-described range, it is possible to suppress a decrease in water repellency due to oxygen atoms and to make the laminate highly water repellent.

  Here, the component ratio in each part of the water-repellent material of the present invention is a value measured by XPS (X-ray Photoelectron Spectroscopy). The analysis method by XPS will be described below. When a solid surface is irradiated with X-rays in a vacuum, electrons are scattered from the surface atoms given energy by the X-rays. These electrons are called photoelectrons because they are generated by irradiation with light such as X-rays. Since this photoelectron has energy specific to the element, qualitative analysis and quantitative analysis of the element can be performed by measuring the energy distribution. In addition, photoelectrons generated deep from the surface lose their energy before coming out to the surface and are difficult to measure. The escape depth of electrons having a kinetic energy of 1000 eV is several nm (tens of atomic layers). Therefore, it is possible to obtain information on the outermost surface.

  Furthermore, in order to measure the depth, the surface may be sputtered with ions such as argon. Since selective sputtering occurs depending on the type of element, a known correction method may be performed for quantification.

  Further, the water repellent material in the present invention may be a self-assembled monomolecular film in addition to the above. Hereinafter, the self-assembled monolayer will be described.

  A self-assembled monolayer usually forms a monolayer spontaneously while organic molecules gather spontaneously at the solid / liquid interface or solid / gas interface to form an aggregate. An organic thin film. For example, when a substrate made of a specific material is exposed to a solution or vapor of an organic molecule having a high chemical affinity with the substrate material, the organic molecule is chemically reacted and adsorbed on the surface of the substrate. If the organic molecule consists of two parts, a functional group with high chemical affinity and an alkyl group that does not cause any chemical reaction with the substrate, the molecule reacts when the functional group with high affinity is at its end. The sex terminal is adsorbed with the substrate side facing and the alkyl group facing the outside. When alkyl groups gather together, the whole becomes stable, so organic molecules gather spontaneously during the process of chemisorption. Since molecular adsorption requires a chemical reaction between the substrate and the terminal functional group, once the surface of the substrate is covered with organic molecules to form a monolayer, molecular adsorption is performed thereafter. Does not happen. As a result, an organic monomolecular film in which molecules are densely gathered and aligned is formed. In the present invention, such a film is a self-assembled monolayer. Here, the reactive terminal group bonded to the substrate is an adsorbing group, and the group oriented to the outside is an aligning group.

Here, the self-assembled monolayer is preferably formed of a compound represented by the following general formula (1).
R ¹ XR ² (1)
(Where R ¹ represents an alkyl group, an aryl group, etc .; R ² represents hydrogen, halogen, —OR ³ (R ³ represents an alkyl group, an allyl group, an aryl group, etc.), etc.) X is Si, Ti, Al, C or S.

R ¹ is an orientation group such as an alkyl group or an aryl group (benzene ring). Although carbon number is not specifically limited, Preferably it is 1-50, More preferably, it is 1-30. Further, it may partially contain a branched chain, multiple bonds and the like. Further, the group bonded to carbon may contain halogen such as fluorine and chlorine, hydrogen, nitrogen and the like. When R ¹ is the above-mentioned orientation group, the self-assembled monomolecular film of the present invention has high water repellency.

R ² is an adsorbing group such as hydrogen, halogen, or —OR ³ . Here, the group bonded to carbon may contain halogen such as fluorine and chlorine, hydrogen, nitrogen and the like.

  Examples of the self-assembled monolayer forming material shown above include octadecyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrichlorosilane, octadecylmethyldiethoxysilane, octadecyldimethylmethoxysilane, octadecylmethyldimethoxysilane, octadecylmethoxydichlorosilane. , Octadecylmethyldichlorosilane, octadecyldimethyl (dimethylamino) silane, octadecyldimethylchlorosilane, nonylchlorosilane, octenyltrichlorosilane, octenyltrimethoxysilane, octylmethyldichlorosilane, octylmethyldiethoxysilane, octyltrichlorosilane, octyltriethoxy Silane, octyltrimethoxysilane, pentafluorophenylpropyl trichloro Silane, pentafluorophenylpropyltrimethoxysilane, pentyltriethoxysilane, pentyltrichlorosilane, phenethyltrichlorosilane, phenethyltrimethoxysilane, phenyldichlorosilane, phenyldiethoxysilane, phenylethyldichlorosilane, phenylmethyldimethoxysilane, phenyltrimethoxysilane , Phenyltrichlorosilane, phenyltriethoxysilane, propyltriethoxysilane, propyltrimethoxysilane, propyltrichlorosilane, tetradecyltrichlorosilane, (3,3,3-trifluoropropyl) dimethylchlorosilane, (3,3,3- (Trifluoropropyl) trichlorosilane, (3,3,3-trifluoropropyl) trimethoxysilane, (3,3,3-trif Olopropyl) triethoxysilane, 3,3,4,4,5,5,6,6,6-nonafluorohexylmethyldichlorosilane, 3,3,4,4,5,5,6,6,6-nona Fluorohexyltrichlorosilane, isooctyltrimethoxysilane, isobutylmethyldichlorosilane, isobutyltriethoxysilane, isobutyltrichlorosilane, hexyltrichlorosilane, hexyltriethoxysilane, hexyltrimethoxysilane, hexenyltrichlorosilane, hexyldichlorosilane, hexadecyltri Chlorosilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, heptyltrichlorosilane, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane, (heptadecafluoro-1, 1,2,2-tetrahydrodecyl) trichlorosilane, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) methyldichlorosilane, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) dimethylchlorosilane , Eicosyltrichlorosilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, dodecyltrichlorosilane, dodecylmethyldichlorosilane, dodecyldimethylchlorosilane, diphenyldiethoxysilane, diphenyldichlorosilane, diphenyldiethoxysilane, diphenyldimethoxysilane, dimethoxymethyl- 3,3,3-trifluoropropylsilane, decylmethyldichlorosilane, decyltrichlorosilane, decyltriethoxysilane, decyltrimethoxysilane, decyldimethyl Lorosilane, cyclohexylmethyltrichlorosilane, cyclohexyltrichlorosilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3-chloropropyltrichlorosilane, chlorophenyltrichlorosilane, butyltrimethoxysilane And butyltrichlorosilane.

  In the present invention, among them, octadecyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrichlorosilane, nonylchlorosilane, octenyltrichlorosilane, octenyltrimethoxysilane, octyltrichlorosilane, octyltriethoxysilane, octyltrimethoxysilane, pentafluoro Phenylpropyltrichlorosilane, pentafluorophenylpropyltrimethoxysilane, pentyltriethoxysilane, pentyltrichlorosilane, phenethyltrichlorosilane, phenethyltrimethoxysilane, phenyltrimethoxysilane, phenyltrichlorosilane, phenyltriethoxysilane, propyltriethoxysilane, propyltri Methoxysilane, propyltrichlorosilane, tetradecylto Chlorosilane, (3,3,3-trifluoropropyl) trichlorosilane, (3,3,3-trifluoropropyl) trimethoxysilane, (3,3,3-trifluoropropyl) triethoxysilane, 3,3, 4,4,5,5,6,6,6-nonafluorohexyltrichlorosilane, isooctyltrimethoxysilane, isobutyltriethoxysilane, isobutyltrichlorosilane, hexyltrichlorosilane, hexyltriethoxysilane, hexyltrimethoxysilane, hexenyl Trichlorosilane, hexadecyltrichlorosilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, heptyltrichlorosilane, (heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane, (heptadeca (Luoro-1,1,2,2-tetrahydrodecyl) trichlorosilane, eicosyltrichlorosilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, dodecyltrichlorosilane, dimethoxymethyl-3,3,3-trifluoropropylsilane, decyl Trichlorosilane, decyltriethoxysilane, decyltrimethoxysilane, decyldimethylchlorosilane, cyclohexylmethyltrichlorosilane, cyclohexyltrichlorosilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3-chloropropyltrichlorosilane, chlorophenyl Trichlorosilane, butyltrimethoxysilane, and butyltrichlorosilane are preferred.

  Especially octadecyltrimethoxysilane, octadecyltriethoxysilane, octadecyltrichlorosilane, octyltriethoxysilane, phenyltriethoxysilane, (tridecafluoro-1,1,2,2-tetrahydrooctyl) triethoxysilane, isobutyltrimethoxysilane, (Heptadecafluoro-1,1,2,2-tetrahydrodecyl) triethoxysilane, dodecyltriethoxysilane, and 3-chloropropyltrimethoxysilane are more preferable.

  When the water repellent material alone forms a flat layer, the contact angle between water and the flat layer is shown in FIG. From the viewpoint of high water repellency, the planar layer preferably has a contact angle with water of 70 to 120 °, more preferably 100 to 120 °.

The contact angle is measured using a contact angle measuring device (model number CA-Z, manufactured by Kyowa Interface Chemical Co., Ltd.). Specifically, one drop (a constant amount) of pure water is dropped on the flat layer surface of the object to be measured, and the shape of the water drop is visually observed using a microscope or a CCD camera after a predetermined time (about 10 seconds). The contact angle is physically obtained by observing.
(Water repellent carbon material)
The water repellent carbon material of the present invention is formed by imparting a water repellent material to a part of the surface of the carbon material.

The applying method is preferably a gas phase method. By using a vapor phase method, a water repellent material that is normally non-conductive can be formed so as not to cover at least the entire surface of the carbon material, so that electrons move to the separator via the carbon material. Can do. As a result, the electrode catalyst layer of the present invention can obtain water repellency while having conductivity. The average amount of the water repellent material is not limited, and is usually 0 with respect to 100 parts by weight of the carbon material. 0.1 to 100 parts by weight, preferably 1 to 50 parts by weight.

  The ratio (surface area) of the water repellent material to the surface of the carbon material is not limited as long as it is within the range where the water repellent performance is exhibited, and is appropriately determined according to the purpose.

The preferred average thickness of the water repellent material is usually in the range of 1 nm to 50 nm, in particular in the range of 1 nm to 20 nm, especially 1 nm to 5 nm. The gas phase method is particularly limited as long as it is a method via the gas phase. Instead, a known method can be used. For example, chemical vapor deposition method (CVD method) such as reactive sputtering method, reactive vapor deposition method, physical vapor deposition method (PVD method) such as ion plating method, plasma CVD method, thermal CVD method, laser CVD method Etc. Among these, the CVD method is preferable from the viewpoints of three-dimensional deposition, adhesion to a substrate, and productivity. Furthermore, a plasma CVD method and a thermal CVD method are more preferable. The plasma CVD method may be any method that generates plasma from the reaction gas in the reaction apparatus by discharging. The thermal CVD method may be any method that evaporates the reaction gas in the reaction apparatus by increasing the temperature.

In particular, a water-repellent carbon material formed by a plasma CVD method using an organometallic compound having a carbon-containing group, a hydrocarbon compound, a fluorine-containing compound, or the like, or a thermal CVD method using the self-assembled monomolecular film. The formed water-repellent carbon material is preferable.
(Water repellent catalyst material)
The water repellent catalyst material of the present invention is formed by imparting a water repellent material to a part of the surface of a catalyst material in which a catalytically active component is supported on a carbon material.

The application method is preferably a gas phase method. By using the vapor phase method, a water repellent material that is usually non-conductive can be formed so as not to cover at least the entire surface of the catalyst material, so that electrons move to the separator via the catalyst material. Can do. As a result, the electrode catalyst layer of the present invention can obtain water repellency while having electrical conductivity. The average amount of the water-repellent material is not limited and is usually 0. 1 to 100 parts by weight, preferably 1 to 50 parts by weight.

  The ratio (surface area) of the water repellent material and the catalytically active component occupying the surface of the carbon material is not limited as long as it is within the range where the water repellent performance and the catalytic effect are exhibited, and is appropriately determined according to the purpose.

The preferred average thickness of the water repellent material is usually in the range of 1 nm to 50 nm, in particular in the range of 1 nm to 20 nm, especially 1 nm to 5 nm. The gas phase method is the same as described above.

In addition, a water-repellent catalyst material formed by a plasma CVD method using an organometallic compound having a carbon-containing group, a hydrocarbon compound or a fluorine-containing compound, or a thermal CVD method using the self-assembled monomolecular film. The formed water repellent catalyst material is preferred.
(Water repellent electrode catalyst layer)
The water-repellent electrode catalyst layer of the present invention comprises 1) the solid polymer electrolyte, catalyst material and water-repellent carbon material, 2) the solid polymer electrolyte and water-repellent catalyst material, and 3) the solid polymer electrolyte and water-repellent carbon. Any of the raw material and the water-repellent catalyst material may be included.

  The water-repellent electrode catalyst layer of the present invention may contain a carbon material that does not have water repellency, that is, a carbon material that is not provided with a water-repellent material on the surface, as necessary. Further, the water repellent electrode catalyst layer of 2) or 3) may contain a catalyst material that does not have water repellency, that is, a catalyst material that is not provided with a water repellent material on the surface, as necessary.

  The thickness of the electrode catalyst layer is usually 1 μm to 50 μm, preferably 5 μm to 20 μm.

In the present invention, when water is present on the surface of the water-repellent electrode catalyst layer, the electrode catalyst layer preferably has a contact angle with water of 70 to 170 °, preferably 120 ° or more. More preferred. In addition, the measurement method of the contact angle with water here is measured by the method mentioned above.
(Water repellent catalyst layer-electrolyte assembly)
In the water-repellent catalyst layer-electrolyte assembly, an electrode catalyst layer and a gas diffusion layer are sandwiched in order on both sides of the electrolyte membrane.

  In the water-repellent catalyst layer-electrolyte assembly of the present invention, at least one of the two electrode catalyst layers sandwiched is the above-described water-repellent electrode catalyst layer. The water repellent catalyst layer is sandwiched so that the water repellent layer is in contact with the electrolyte membrane.

  The electrolyte membrane is not particularly limited as long as it has hydrogen ion conductivity, and can be appropriately employed depending on the purpose. For example, a perfluorocarbon sulfonic acid polymer (PFS polymer) in which the C—H bond of a hydrocarbon ion exchange membrane is substituted with fluorine may be mentioned. The introduction of fluorine atoms having a high electronegativity into the PFS-based polymer makes it very chemically stable and has a high degree of sulfonic acid group dissociation, so that high ionic conductivity can be realized. Among these, specifically, Nafion (registered trademark, manufactured by DuPont), Flemion (registered trademark, manufactured by Asahi Glass), and Aciplex (registered trademark, manufactured by Asahi Kasei) are preferable.

  The thickness of the electrolyte membrane is usually 10 μm to 250 μm, preferably 15 μm to 175 μm.

The gas diffusion layer is not particularly limited as long as it has gas permeability and conductivity, and examples thereof include carbon paper made of carbon paper using conductive fibers, carbon cloth, carbon felt, and the like.
(Unit cell)
The unit cell for the solid fuel cell of the present invention may be any unit cell provided with the membrane-electrode assembly.

  The unit cell of the present invention is obtained by sandwiching the membrane-electrode assembly with a separator.

  A separator in particular is not restrict | limited, A well-known thing can be used. Examples of the material of the separator include metals such as stainless steel, copper, titanium, aluminum, rhodium, tantalum, tungsten, and gold, or an alloy containing at least one of them; graphite; a carbon compound in which carbon is kneaded into a resin. . Among these, from the viewpoints of strength, thinning of the fuel cell, and the like, the above metals or alloys containing at least one of them are preferable, and stainless steel and titanium are more preferable.

The separator may be subjected to a surface treatment such as plating. These surface treatments can be performed according to a known method.
(Fuel cell)
The polymer electrolyte fuel cell is formed by stacking unit cells, and the polymer electrolyte fuel cell of the present invention only needs to have one or more unit cells.
2. Method for producing water-repellent electrode catalyst layer The method for producing the water-repellent electrode catalyst layer of the present invention comprises:
(1) A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of applying a water repellent material to a part of a carbon material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte, a catalyst material, and a water-repellent carbon material,
2) The catalyst material comprises a carbon material carrying a catalytically active component,
3) The water-repellent carbon material has a water-repellent material on a part of the surface of the carbon material.
Manufacturing method of water-repellent electrode catalyst layer,
(2) A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of applying a water-repellent material to a part of the catalyst material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte and a water-repellent catalyst material,
2) The water-repellent catalyst material has a water-repellent material on a part of the surface of the catalyst material obtained by supporting a catalytic active component on a carbon material.
A method for producing a water repellent electrode catalyst layer, or (3) a method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, wherein a water repellent property is applied to a part of the surface of a carbon material and / or catalyst material by a gas phase method. Including the step of applying a material,
1) The electrode catalyst layer includes a solid polymer electrolyte, a water repellent carbon material, and a water repellent catalyst material,
2) The water-repellent carbon material has a water-repellent material on a part of the surface of the carbon material,
3) The water-repellent catalyst material has a water-repellent material on a part of the surface of a catalyst material in which a catalytically active component is supported on a carbon material.
This is a method for producing a water-repellent electrode catalyst layer.
(Water repellent material forming process)
The formation step of the water repellent material in the present invention is a step of forming a catalyst material on a part of the surface of the carbon material and / or the catalyst material described above by a vapor phase method.

The gas phase method for forming a water repellent material on a part of the carbon material and / or catalyst material surface is not particularly limited as long as the method is performed via the gas phase. For example, film forming methods such as a reactive sputtering method, a reactive vapor deposition method, a PVD method such as an ion plating method, a CVD method such as a thermal CVD method, a plasma CVD method, and a laser CVD method can be given. In the present invention, the CVD method is preferable.
(1) In particular, a desired material can be formed on the surface of the carbon material at a low temperature (in the range of about -20 to 200 ° C.) that does not cause thermal damage to the carbon material or the catalyst material. From the viewpoint that the type and physical properties of the material obtained can be controlled by the film forming pressure, input power, and the like, the plasma CVD method is preferable.

  Specific conditions for forming the water repellent material in the plasma CVD method of the present invention will be described.

  Although the temperature in particular of a carbon material or a catalyst material is not restrict | limited, Usually, it exists in the range of -20-100 degreeC, Preferably it exists in the range of -10-50 degreeC.

  The raw material gas is not particularly limited as long as it is a gas containing a component contained in a desired water repellent material.

  The energy band of the plasma CVD method is not particularly limited, and high frequency, super high frequency, microwave, or the like may be used.

Here, when the water repellent material is formed by the plasma CVD method, the water repellent material is at least one of (i) an organometallic compound having a carbon-containing group (ii) a hydrocarbon compound and (iii) a fluorine-containing compound. Preferably there is. Thereby, a water-repellent material having high water repellency can be formed on a part of the carbon material. Hereinafter, the source gas used for these will be described.
(I) Organometallic compound having a carbon-containing group As a gas for forming a water-repellent material composed of an organometallic compound having a carbon-containing group, if it contains a metal element such as an alkyl group and Si, Ti, Al, There is no particular limitation.

  Specific examples of the organosilicon compound gas include hexamethyldisiloxane (HMDSO), 1,1,3,3-tetramethyldisiloxane (TMDSO), tetramethylsilane (TMS), vinyltrimethoxysilane, and vinyltrimethyl. Silane, tetramethoxysilane (TMOS), methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, tetraethoxysilane (TEOS), dimethyldiethoxysilane, methyldimethoxysilane, methyldiethoxysilane, hexamethyldisilazane, etc. are preferred In addition to these, one or more conventionally known ones such as tetramethyldisiloxane and normal methyltrimethoxysilane can be used.

  Among these, from the viewpoint of further improving water repellency, an organosilicon compound having a large number of carbon-silicon bonds in the molecule is preferably used. Specifically, hexamethyldisiloxane (HMDSO), 1,1,3,3-tetramethyldisiloxane (TMDSO), tetramethylsilane (TMS), vinyltrimethoxysilane, vinyltrimethylsilane, methyltrimethoxysilane, Examples thereof include dimethyldimethoxysilane, trimethylmethoxysilane, dimethyldiethoxysilane, methyldimethoxysilane, methyldiethoxysilane, and hexamethyldisilazane.

Furthermore, from the viewpoint of having more carbon-silicon bonds in the molecule, hexamethyldisiloxane (HMDSO; (CH ₃ ) ₃ SiOSi (CH ₃ ) ₃ ), tetramethyldisiloxane (TMDSO; (CH ₃ ) ₂ HSiOSiH (CH ₃ ) ₂ ) and tetramethylsilane (TMS; Si (CH ₃ ) ₄ ) are more preferred.
(Ii) Hydrocarbon-based material The hydrocarbon-based material is not particularly limited as long as it is composed of C and H. Preferable materials include CH ₄ , C ₂ H ₂ , C ₂ H ₄ , C ₃ H ₈ or a mixed gas thereof, more preferably C ₂ H ₂ or C ₂ H _4. .
(Iii) Fluorine-containing compound material The fluorine-containing compound material is not particularly limited as long as it contains fluorine, but is preferably a fluorine-containing organic compound, for example, CF ₄ , C ₂ F ₄ , C ₂ F ₆ , C ₃ F ₆ , C ₃ F ₈ , C ₅ F ₈ or a mixed gas thereof can be exemplified, and among these, C ₂ F ₄ or C ₃ F ₈ is particularly preferable.

An organic compound having many carbon-silicon bonds is used as the organosilicon compound gas in the source gas, and the temperature of the base material at the start, the input power in the plasma generating means, the pressure, and the like are within the above ranges. Thus, a more excellent water repellent material can be formed. This is because the compounds (i) and (iii) have low decomposability of the organosilicon compound gas, and an alkyl group (usually in the range of 1 to 30 carbon atoms) or fluorine is taken into the film. This is based on the reason that it becomes easier. The compound (ii) is considered to be based on the reason that a material having a high water-repellent effect can be obtained as a result of the water-repellent material being composed of only CH bonds.
(2) It is also preferable to form the water repellent material on a part of the surface of the carbon material or the catalyst material by a thermal CVD method among the CVD methods.

  This is because the thermal CVD method vaporizes the raw material, sends the material uniformly onto the carbon material, and performs reactions such as oxidation, reduction, substitution, etc. This is based on the reason that the water repellent material can be uniformly formed on the top.

  As preferable conditions for the thermal CVD method in the present invention, the higher the heat resistance temperature of the carbon material or the catalyst material, the better. However, it is particularly preferable to be within the range of 50 ° C to 200 ° C. This is based on the reason that the presence of moisture or oxygen in the reaction system further promotes the hydrolysis reaction of the alkoxy group of the water repellent material substance and increases the reactivity with the carbon material.

Since the material of the water repellent material by the thermal CVD method in the present invention is the same as the description of the water repellent material of the carbon material or the catalyst material described above, description thereof is omitted here.
(Water repellent electrode catalyst layer forming step)
The water-repellent electrode catalyst layer of the present invention comprises the above substances, that is, (1) the solid polymer electrolyte, catalyst material, and water-repellent carbon material, 2) the solid polymer electrolyte and water-repellent catalyst material, or 3) the solid polymer. It is manufactured by mixing any one of an electrolyte, a water repellent carbon material, and a water repellent catalyst material.

  The mixing method is not particularly limited, and a known method is used. For example, the above raw materials may be mixed in an organic solvent such as 1-propanol, 2-propanol, 1-butanol, 2-butanol, and 3-butanol. Thereby, a catalyst paste can be produced.

  Next, the catalyst paste prepared by the above mixing may be applied to a transfer substrate and solidified.

  The method for applying the catalyst paste can be appropriately selected according to the viscosity, solid content, etc. of the catalyst paste, and is not particularly limited. For example, general methods such as knife coater, bar coater, spray, dip coater, spin coater, roll coater, die coater, curtain coater, and screen printing can be used.

The present invention will be described more specifically with reference to the following examples and comparative examples. The present invention is not limited to the following embodiment.
Example 1
(Water repellent material formation by thermal CVD process)
Carbon material (Ketjen Black EC, manufactured by Lion) and about 0.2 ml of octadecyltrimethoxysilane (00256 manufactured by Tokyo Chemical Industry Co., Ltd.) placed in a glass container are placed in a Teflon (registered trademark) container. did. Thereafter, the film was left in an oven at 100 ° C. for 5 hours to form a water repellent material (hereinafter abbreviated as ODS-SAM) by thermal CVD. This produced the water-repellent carbon material.

  After the formation of the water repellent material, the material properties of the water repellent carbon material were evaluated by XPS, and the presence of Si was confirmed in the water repellent material. The evaluation by XPS was carried out using XPS220iXL (manufactured by ESCALAB) under the conditions of using MgKα, 15 kV, 20 mA (300 W).

  In the preparation of the electrode catalyst layer (air electrode), 100 mg of the above water-repellent carbon material particles, 10 g of platinum-supporting carbon (trade name: TEC10E50E, manufactured by Tanaka Kikinzoku Kogyo), and 5 wt% Nafion solution (trade names: Nafion SE20042, DuPont) A paste for electrode catalyst layer preparation (for air electrode) was prepared by mixing 100 g with 100 g of alcohol solvent of 1-propanol.

  In the production of the electrode catalyst layer (fuel electrode), 10 g of a catalyst material (PtRu 53.3 wt%, TEC61E54 manufactured by Tanaka Kikinzoku Kogyo Co., Ltd.) on which a platinum ruthenium alloy is supported on a carbon material as a catalyst active component, and a 5 wt% Nafion solution (a binder) A catalyst paste for preparing an electrode catalyst layer (for a fuel electrode) was prepared by stirring and mixing with 100 g of DuPont solvent propanol) using a disperser.

  Next, each of the electrode catalyst preparation pastes prepared above was applied onto a PET film (E3120, manufactured by Toyobo Co., Ltd., thickness 12 μm) with a doctor blade so that the thickness after drying was 10 μm. . This was dried at 90 ° C. for 30 minutes in an air atmosphere to produce an electrode catalyst layer for the air electrode and the fuel electrode.

Next, the electrode catalyst layer for the air electrode and the fuel electrode is hot-pressed on a hydrogen ion conductive polymer electrolyte membrane (Nafion 112, manufactured by DuPont) under the conditions of 1550 ° C. and 3 MPa, thereby obtaining a catalyst layer-electrolyte membrane. A joined body was prepared.
Example 2
(Water repellent material formation by thermal CVD process)
Platinum-supported carbon powder (trade name: TEC10E50E, manufactured by Tanaka Kikinzoku Kogyo Co., Ltd.) and about 0.2 ml of octadecyltrimethoxysilane (00256 manufactured by Tokyo Chemical Industry Co., Ltd.) in a glass container Installed inside. Next, by leaving it in an oven at 100 ° C. for 5 hours, a water repellent material was formed by thermal CVD.

  After forming the water repellent material, it was confirmed by XPS composition analysis that the water repellent material was formed.

In preparation of the catalyst layer (for air electrode), 0.5 g of the above water-repellent platinum catalyst material, 9.5 g of untreated platinum catalyst material, and 5 g of Nafion solution (trade name: Nafion SE20042, manufactured by DuPont) 100 g Was mixed at 100 g in an alcohol solvent that was 1-propanol to prepare an electrode catalyst layer preparation paste. After the formation of the electrode catalyst layer, an electrode catalyst layer-electrolyte membrane assembly was produced in the same manner as in Example 1.
Comparative Example 1
An electrode catalyst layer was formed using a carbon material not subjected to water repellent treatment in the same manner as in Example 1 to prepare an electrode catalyst layer-electrolyte membrane assembly.
Test evaluation Electrode catalyst layer-Place the electrode substrate (carbon paper made of carbon fiber, TGP-H-090, manufactured by Toray Industries, Inc.) on both sides of the electrolyte membrane laminate, and sandwich the cell with separators. Produced. The unit cell was continuously operated for 500 hours at a constant current of 300 mA, and the battery performance of the catalyst layer-electrolyte membrane laminate produced using each catalyst layer transfer sheet was evaluated.

  As a result, Examples 1 and 2 showed a small decrease in battery current even after 500 hours, while Comparative Example 1 showed a large decrease in current. This is because the water-repellent material can discharge water generated by the battery reaction to the outside of the system, and the performance is improved.

FIG. 1 shows the contact angle between the layer and water.

Explanation of symbols

1 water 2 layers

Claims (19)

An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte, a catalyst material, and a water-repellent carbon material,
2) The catalyst material comprises a carbon material carrying a catalytically active component,
3) The water-repellent carbon material is formed by imparting a water-repellent material to a part of the surface of the carbon material by a vapor phase method.
A water-repellent electrode catalyst layer characterized by the above. An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte and a water-repellent catalyst material,
2) The water-repellent catalyst material is formed by applying a water-repellent material to a part of the surface of a catalyst material obtained by supporting a catalytic active component on a carbon material by a gas phase method.
A water-repellent electrode catalyst layer characterized by the above. An electrode catalyst layer for a polymer electrolyte fuel cell,
1) The electrode catalyst layer includes a solid polymer electrolyte, a water repellent carbon material, and a water repellent catalyst material,
2) The water-repellent carbon material is formed by imparting a water-repellent material to a part of the surface of the carbon material,
3) The water-repellent catalyst material is formed by imparting a water-repellent material to a part of the surface of the catalyst material obtained by supporting a catalytically active component on a carbon material,
4) The application of the water-repellent material in 2) and / or 3) is performed by a vapor phase method.
A water-repellent electrode catalyst layer characterized by the above. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of claims 1 to 3, wherein the vapor phase method is a chemical vapor deposition method. The solid polymer form according to any one of claims 1 to 4, wherein the water repellent material is at least one of 1) an organometallic compound having a carbon-containing group, 2) a hydrocarbon compound, and 3) a fluorine-containing compound. Water repellent electrode catalyst layer for fuel cells. An organometallic compound having a carbon-containing group is represented by Si _x O _y C _z Hα (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ z ≦ 50, 1 ≦ α ≦ 122). 6. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to claim 5, which is an organic silicon material and / or a polymer thereof. The fluorine-containing compound is 1) Si _x O _y C _z HαFβ (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 1 ≦ z ≦ 50, 1 ≦ α ≦ 122, 1 ≦ β ≦ 122) 2) Si _x O _y HαFβ (where 1 ≦ x ≦ 10, 0 ≦ y ≦ 10, 0 ≦ α ≦ 21, 1 ≦ β ≦ 22) 3) C _x O _y H _z Fα (where 1 ≦ x ≦ 50, 0 ≦ y ≦ 10, 0 ≦ z ≦ 102, 0 ≦) The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to claim 5, which is at least one of a fluorine-containing hydrocarbon-based material and / or a polymer thereof represented by α ≦ 102. The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of claims 1 to 4, wherein the water-repellent material comprises a self-assembled monolayer. The self-assembled monolayer has the following general formula (1):
R ¹ XR ² (1)
(Where R ¹ represents an alkyl group or an aryl group. R ² represents hydrogen, halogen, or —OR ³ (R ³ represents an alkyl group, an allyl group, or an aryl group). X represents Si, Ti, Al, C or S.)
The water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to claim 8, which is formed of a compound represented by the formula: The water repellent material has a contact angle with water of 70 to 170 °, and the water repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of claims 1 to 9. A catalyst layer-electrolyte membrane assembly for a polymer electrolyte fuel cell, wherein the water-repellent electrode catalyst layer according to any one of claims 1 to 10 is joined to an electrolyte membrane. A unit cell for a polymer electrolyte fuel cell, comprising the catalyst layer-electrolyte membrane assembly according to claim 11. A polymer electrolyte fuel cell comprising the unit cell according to claim 12. A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of applying a water repellent material to a part of a carbon material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte, a catalyst material, and a water-repellent carbon material,
2) The catalyst material comprises a carbon material carrying a catalytically active component,
3) The water-repellent carbon material has a water-repellent material on a part of the surface of the carbon material.
A method for producing a water-repellent electrode catalyst layer. A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of applying a water-repellent material to a part of the catalyst material surface by a vapor phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte and a water-repellent catalyst material,
2) The water-repellent catalyst material has a water-repellent material on a part of the surface of the catalyst material obtained by supporting a catalytic active component on a carbon material.
A method for producing a water-repellent electrode catalyst layer. A method for producing an electrode catalyst layer for a polymer electrolyte fuel cell, comprising a step of imparting a water repellent material to a part of a surface of a carbon material and / or a catalyst material by a gas phase method,
1) The electrode catalyst layer includes a solid polymer electrolyte, a water repellent carbon material, and a water repellent catalyst material,
2) The water-repellent carbon material has a water-repellent material on a part of the surface of the carbon material,
3) The water-repellent catalyst material has a water-repellent material on a part of the surface of a catalyst material in which a catalytically active component is supported on a carbon material.
A method for producing a water-repellent electrode catalyst layer. The method for producing a water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to any one of claims 14 to 16, wherein the vapor phase method is a chemical vapor deposition method. The method for producing a water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to claim 17, wherein the chemical vapor deposition method is plasma CVD. The method for producing a water-repellent electrode catalyst layer for a polymer electrolyte fuel cell according to claim 17, wherein the chemical vapor deposition method is thermal CVD.

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