KR20170037430A - Membrane electrode assembly, fuel cell comprising the membrane electrode assembly and method for manufacturing the membrane electrode assembly - Google Patents

Abstract

The present invention relates to a membrane electrode assembly, a fuel cell comprising the same, and a method for manufacturing the membrane electrode assembly. The membrane electrode assembly comprises: a polymer electrolyte membrane having a plurality of protrusions on the surface thereof; an anode catalyst layer formed on one surface of the polymer electrolyte membrane; and a cathode catalyst layer formed on the other surface of the polymer electrolyte membrane. According to the present invention, an interfacial adhesive force between a catalyst layer and a polymer electrolyte membrane of an electrode can be improved.

Description

TECHNICAL FIELD [0001] The present invention relates to a membrane electrode assembly, a fuel cell including the membrane electrode assembly, and a method for manufacturing the membrane electrode assembly. [0002]

TECHNICAL FIELD The present invention relates to a membrane electrode assembly, a fuel cell including the membrane electrode assembly, and a method of manufacturing the membrane electrode assembly.

Recently, as the exhaustion of existing energy resources such as oil and coal is predicted, interest in energy that can replace them is increasing. As one of such alternative energies, fuel cells have attracted particular attention due to their advantages such as high efficiency, no emission of pollutants such as NOx and SOx, and abundant fuel.

A fuel cell is a power generation system that converts the chemical reaction energy of a fuel and an oxidant into electric energy. Hydrogen, hydrocarbons such as methanol and butane are used as fuel, and oxygen is used as an oxidant.

BACKGROUND ART Fuel cells include a polymer electrolyte fuel cell (PEMFC), a direct methanol fuel cell (DMFC), a phosphoric acid fuel cell (PAFC), an alkaline fuel cell (AFC), a molten carbonate fuel cell (MCFC) And a battery (SOFC). Among them, polymer electrolyte fuel cells have been actively studied because they have high energy density and high output. Such a polymer electrolyte fuel cell differs from other fuel cells in that it uses a solid polymer electrolyte membrane instead of a liquid electrolyte.

Korean Patent Publication No. 2003-0076057

The present invention provides a membrane electrode assembly, a fuel cell including the membrane electrode assembly, and a method of manufacturing the membrane electrode assembly.

The present invention relates to a polymer electrolyte membrane having a plurality of protrusions on its surface; An anode catalyst layer provided on one surface of the polymer electrolyte membrane; And a cathode catalyst layer provided on the other surface of the polymer electrolyte membrane, wherein the protrusions are provided with an enlarged portion in which the protrusions are increased in width from the inner side where the protrusions are in contact with the polymer electrolyte membrane to the outward direction in which the protrusions protrude Thereby providing a membrane electrode assembly.

The present invention also provides a fuel cell including the membrane electrode assembly.

The present invention also provides a method of manufacturing a polymer electrolyte membrane, comprising: preparing a polyelectrolyte membrane having a plurality of projections on a surface thereof; Forming an anode catalyst layer on one side of the polymer electrolyte membrane; And forming a cathode catalyst layer on the other surface of the polymer electrolyte membrane, wherein the protrusion is provided with a protuberance portion in which a width of the protuberance increases from an inner side where the protrusion is in contact with the polyelectrolyte membrane to an outward direction in which the protrusion protrudes Wherein the membrane electrode assembly is a membrane electrode assembly.

The membrane electrode assembly of the present invention can improve the interfacial adhesion between the catalyst layer of the electrode and the polymer electrolyte membrane.

The membrane electrode assembly of the present invention can prevent deterioration of the performance of the battery due to interfacial separation between the catalyst layer of the electrode and the polymer electrolyte membrane.

The membrane electrode assembly of the present invention may have an increased contact area between the electrode and the polymer electrolyte membrane to improve the property of transferring the substance.

The membrane electrode assembly of the present invention can improve the initial and long-term performance of a fuel cell.

1 is a schematic view showing an electricity generation principle of a fuel cell.
2 is a schematic view showing a structure of a membrane electrode assembly according to an embodiment of the present invention.
3 is a schematic view showing one embodiment of a fuel cell.
4 is a flow chart of a method for producing a polymer electrolyte membrane according to the first embodiment of the present invention and a scanning electron microscope (SEM) image of the polymer electrolyte membrane thus produced.
5 is a flow chart of a method for producing a polymer electrolyte membrane according to a second embodiment of the present invention and a scanning electron microscope (SEM) image of the polymer electrolyte membrane thus produced.
6 is a flowchart of a method for producing a polymer electrolyte membrane according to a third embodiment of the present invention.
FIG. 7 is a scanning electron microscope (SEM) image of the polymer electrolyte membrane prepared in Comparative Example 2. FIG.

Hereinafter, the present invention will be described in detail.

FIG. 1 schematically shows an electricity generating principle of a fuel cell. In a fuel cell, the most basic unit for generating electricity is a membrane electrode assembly (MEA), which includes an electrolyte membrane M and an electrolyte membrane M, And an anode (A) and a cathode (C) formed on both sides of the cathode (C). Referring to Fig. Showing the electricity generating principle of a fuel cell 1, an anode (A) in the hydrogen or methanol, butane and the oxidation of the fuel (F) of the hydrocarbon and so on up the hydrogen ions (H ⁺⁾ and electron (e ^-), such as And the hydrogen ions move to the cathode C through the electrolyte membrane M. In the cathode (C), the hydrogen ions transferred through the electrolyte membrane (M) react with the oxidizing agent (O) such as oxygen, and water (W) is produced. This reaction causes electrons to migrate to the external circuit.

The present invention relates to a polymer electrolyte membrane having a plurality of protrusions on its surface; An anode catalyst layer provided on one surface of the polymer electrolyte membrane; And a cathode catalyst layer provided on the other surface of the polymer electrolyte membrane, wherein the protrusions are provided with an enlarged portion in which the protrusions are increased in width from the inner side where the protrusions are in contact with the polymer electrolyte membrane to the outward direction in which the protrusions protrude Thereby providing a membrane electrode assembly.

2, the membrane electrode assembly may include an electrolyte membrane 10 and a cathode 50 and an anode 51 positioned opposite to each other with the electrolyte membrane 10 interposed therebetween. Specifically, the cathode includes a cathode catalyst layer 20 and a cathode gas diffusion layer 30 sequentially provided from the electrolyte membrane 10, and the anode includes an anode catalyst layer 21 and an anode catalyst layer 21 sequentially provided from the electrolyte membrane 10, And a gas diffusion layer 31.

The polymer electrolyte membrane may have a plurality of projections on its surface.

The protrusion may be provided with a protrusion which increases in width from the inner side where the protrusion is in contact with the polyelectrolyte membrane to the outward direction in which the protrusion protrudes.

The protrusion may be further provided with a width decreasing portion in which the width of the protrusion decreases from the inner side where the protrusion is in contact with the polyelectrolyte membrane to the outward direction in which the protrusion protrudes. The enlarged portion and the reduced width portion of the projection may be provided continuously from the inside in which the projection is in contact with the polymer electrolyte membrane to the outward direction in which the projection protrudes. In this case, the protrusion may be in the form of a body and a mushroom-shaped head provided at an end of the body.

The protrusions may be columnar or line-shaped.

The cross-sectional shape of the projection in a direction parallel to the plane direction of the polymer electrolyte membrane may be circular, elliptical, polygonal, star-shaped, and the like, and is not particularly limited.

The height of the protrusions may be 1 탆 or more and 100 탆 or less. Here, the height of the protrusion means the distance from the bottom of the groove formed by the plurality of protrusions to the end of the protrusion.

The width of the protrusions may be 1 탆 or more and 100 탆 or less. Here, the width of the protrusion means a distance passing through the center of the cross section from one point to the other point in the cross section of the protrusion in the direction parallel to the plane direction of the polymer electrolyte membrane.

The difference between the longest width of the bulged portion and the width of the inside of the projection may be 10 nm or more and 50 탆 or less. In this case, the catalyst layer of the electrode is caught by the protrusion of the polymer electrolyte membrane, so that the interfacial adhesion between the catalyst layer of the electrode and the polymer electrolyte membrane can be improved.

The plurality of protrusions may be provided on at least one surface of the polymer electrolyte membrane. Specifically, the plurality of protrusions may be provided on the entire surface of the polyelectrolyte membrane on which the anode catalyst layer and the cathode catalyst layer are provided.

The thickness of the polymer electrolyte membrane may be 5 占 퐉 or more and 50 占 퐉 or less. In this case, there is an advantage that an optimum state is obtained in terms of minimizing the gas cross over of the electrolyte membrane gas and minimizing the proton ion resistance.

Here, the thickness of the polymer electrolyte membrane means a distance from one surface to the other surface of the polymer electrolyte membrane. When the projections are provided on both sides of the polymer electrolyte membrane, the thickness of the polymer electrolyte membrane means the distance from the bottom of the groove formed by a plurality of projections on one surface to the bottom of the groove formed by the plurality of projections on the other surface.

In one embodiment of the present invention, the polymer electrolyte membrane may be a hydrocarbon-based polymer electrolyte membrane, a partially fluorinated polymer electrolyte membrane, or a fluorinated polymer electrolyte membrane.

In one embodiment of the present invention, the polymer electrolyte composition forming the polymer electrolyte membrane may include a solvent and an ion conductive polymer.

The ion conductive polymer refers to a polymer having ionic conductivity, and may be a polymer having cation conductivity capable of transferring hydrogen cations.

The ion conductive polymer may be a hydrocarbon-based polymer electrolyte membrane, a partially fluorinated polymer electrolyte membrane, or a fluorine-based polymer, and conventional materials known in the art may be used. For example, the ion conductive polymer is selected from the group consisting of Nafion, sulfonated polyether ether ketone, sulfonated polyketone, sulfonated poly (phenylene oxide), sulfonated poly (phenylene sulfide), sulfonated Polysulfones, sulfonated polycarbonates, sulfonated polystyrenes, sulfonated polyimides, sulfonated polyquinoxaline, sulfonated (phosphonite) polyphosphazenes and sulfonated polybenzimidazoles. And may be composed of one or more species.

The content of the ion conductive polymer can be controlled according to the appropriate ion exchange capacity (IEC) value required for the electrolyte membrane for a fuel cell to be applied. In the case of ion-conducting polymer synthesis for electrolyte membrane production for fuel cells, the ion-conducting polymer can be designed by calculating the ion exchange capacity (IEC) meq./g = mmol / g. The polymer content can be selected so as to be within the range of 0.5 < = IEC <

The weight average molecular weight of the ion conductive polymer may be from several tens of thousands to several million. Specifically, the weight average molecular weight of the ion conductive polymer may be selected to be 10,000 or less.

The solvent for the polymer electrolyte membrane is not particularly limited as long as it is a substance capable of reacting with the polymer to dissolve the polymer, and conventional materials known in the art can be used.

The electrolyte membrane may be formed using the above polymer electrolyte composition by a conventional method known in the art. For example, an electrolyte membrane may be formed by casting using the polymer electrolyte composition, or a polymer may be added to the porous polymer membrane. The electrolyte composition may be impregnated into a reinforced membrane.

The membrane electrode assembly may include an anode catalyst layer on one side of the polymer electrolyte membrane and a cathode catalyst layer on the other side of the polymer electrolyte membrane. Specifically, the anode catalyst layer may include an anode catalyst layer provided on one side of the polymer electrolyte membrane, and a cathode catalyst layer provided on the other side of the polymer electrolyte membrane.

The anode catalyst layer and the cathode catalyst layer may be respectively provided on the ends of the projections, filling the space between the projections of the polymer electrolyte membrane. In this case, the interfacial adhesion between the catalyst layer of the electrode and the polymer electrolyte membrane can be improved.

The anode catalyst layer and the cathode catalyst layer may include a catalyst and an ionomer, respectively.

The catalyst may be one of platinum, a transition metal, and a platinum-transition metal alloy, although the type of the catalyst is not limited as long as it can serve as a catalyst in a fuel cell.

Here, the transition metal is an element of Group 3 to Group 11 in the periodic table, and may be any one of ruthenium, osmium, palladium, molybdenum and rhodium.

Specifically, the catalyst may be selected from the group consisting of platinum, ruthenium, osmium, platinum-ruthenium alloy, platinum-osmium alloy, platinum-palladium alloy, platinum-molybdenum alloy and platinum-rhodium alloy. .

The catalysts can be used not only by themselves but also by being supported on a carbon-based carrier.

Examples of the carbon-based support include graphite, carbon black, acetylene black, denka black, cacao black, activated carbon, mesoporous carbon, carbon nanotube, carbon nanofiber, carbon nanohorn, carbon nano ring, A mixture of two or more selected from the group consisting of fullerene (C60) and Super P black (Super P black) is a preferred example.

The ionomer provides a path for ions generated by the reaction between the fuel and the catalyst, such as hydrogen or methanol, to move to the electrolyte membrane. The ionomer may specifically be a sulfonated polymer such as Nafion ionomer or sulfonated polytrifluorostyrene.

Each catalyst ink forming the anode catalyst layer and the cathode catalyst layer may independently include a catalyst, an ionomer and a solvent.

As the solvent contained in the catalyst ink, any one or a mixture of two or more selected from the group consisting of water, butanol, isopropanol, methanol, ethanol, n-propanol, n-butyl acetate and ethylene glycol is preferably used Can be used.

The process of introducing the catalyst layer can be performed by a conventional method known in the art. For example, the catalyst ink may be directly coated on the electrolyte membrane, or a catalyst layer may be formed on the releasable substrate, followed by thermocompression bonding to the electrolyte membrane, The catalyst layer may be formed by removing the substrate or by coating the gas diffusion layer. The method of coating the catalyst ink is not particularly limited, but spray coating, tape casting, screen printing, blade coating, inkjet coating, die coating or spin coating may be used.

The anode gas diffusion layer and the cathode gas diffusion layer are provided on one surface of the catalyst layer, respectively, and serve as a current conductor and have a porous structure as a reaction gas and a water passage. Therefore, the gas diffusion layer may include a conductive base material.

As the conductive base material, any conventional materials known in the art can be used. For example, carbon paper, carbon cloth or carbon felt can be preferably used. It does not.

The thickness of the gas diffusion layer may be 200 탆 or more and 500 탆 or less. In this case, there is an advantage that the reactant gas transfer resistance through the gas diffusion layer is minimized and the optimum state is obtained from the viewpoint of proper water content in the gas diffusion layer.

The present invention provides a fuel cell including the membrane electrode assembly. Specifically, the fuel cell may include at least two membrane electrode assemblies.

Said fuel cell comprising a stack comprising at least two membrane electrode assemblies according to this specification and a separator provided between membrane electrode assemblies; A fuel supply unit for supplying fuel to the stack; And an oxidant supply part for supplying the oxidant to the stack.

3 schematically shows the structure of a fuel cell, which includes a stack 60, an oxidant supply unit 70, and a fuel supply unit 80. [

The stack 60 includes one or more of the membrane electrode assemblies described above and includes a separator interposed therebetween when two or more membrane electrode assemblies are included. The separator serves to prevent the membrane electrode assemblies from being electrically connected and to transfer the fuel and oxidant supplied from the outside to the membrane electrode assembly.

The oxidant supply part 70 serves to supply the oxidant to the stack 60. As the oxidizing agent, oxygen is typically used, and oxygen or air can be injected into the pump 70 and used.

The fuel supply unit 80 serves to supply the fuel to the stack 60 and includes a fuel tank 81 for storing the fuel and a pump 82 for supplying the fuel stored in the fuel tank 81 to the stack 60 Lt; / RTI > As the fuel, gas or liquid hydrogen or hydrocarbon fuel may be used. Examples of hydrocarbon fuels include methanol, ethanol, propanol, butanol or natural gas.

The present invention relates to a method of manufacturing a polymer electrolyte membrane, comprising: preparing a polymer electrolyte membrane having a plurality of projections on a surface thereof; Forming an anode catalyst layer on one side of the polymer electrolyte membrane; And forming a cathode catalyst layer on the other surface of the polymer electrolyte membrane, wherein the protrusion is provided with a protuberance portion in which a width of the protuberance increases from an inner side where the protrusion is in contact with the polyelectrolyte membrane to an outward direction in which the protrusion protrudes Wherein the membrane electrode assembly is a membrane electrode assembly.

In the above-described method for producing a membrane electrode assembly, description of the membrane electrode assembly described above can be cited.

According to a first embodiment of the present invention, the step of preparing the polyelectrolyte membrane comprises: preparing a first mold having a pattern of a relief portion and a relief portion; Forming a substrate having a pattern of embossed portions and embossed portions inverted with the first mold using the first mold; Depositing an inorganic oxide on the surface of the patterned substrate by sputtering an inorganic oxide to produce a second mold; Using the second mold to produce a third mold having a pattern of inverted engraved portions and embossed portions with the second mold; And fabricating a polymer electrolyte membrane having a pattern of an engraved portion and an embossed portion inverted from the third mold using the third mold.

As shown in FIG. 4, after the base 230 having the patterns of the engraved portions and the embossed portions inverted from the first mold is formed by using the first mold 100 having the pattern of the engraved portion and the embossed portion, An inorganic oxide is sputtered on the surface of the formed substrate to produce a second mold 200 in which inorganic oxides are relatively more deposited on the ends of the embossed portions of the substrate. After the third mold 300 having the pattern of the engraved portion and the embossed portion inverted from the second mold is manufactured by using the second mold, the third mold 300 and the inverted engraved portion are formed by using the second mold, A polymer electrolyte membrane having a pattern of embossed portions can be produced.

The first mold may be patterned on a surface of a silicon wiper or glass or the like. Specifically, the first mold may be patterned on one side of the silicon wiper.

The substrate is not particularly limited as long as it is applied onto the surface of the first mold on which the pattern is formed and then cured to form a pattern and is releasable from the first mold, but the substrate may be made of a siloxane polymer or a polyurethane polymer.

The inorganic oxide deposited on the substrate is not particularly limited, but may be, for example, SiO ₂ , Al ₂ O ₃ , and the like.

The inorganic oxide may be sputtered onto the substrate at an output of 50 W to 100 W for 10 minutes to 120 minutes. In this case, as shown in FIG. 4, relatively more inorganic oxide may be deposited on the end portion of the relief portion of the substrate to form a thickening portion where the width of the relief portion is increased.

The third mold may be formed of a siloxane-based polymer or a polyurethane-based polymer, although the third mold is not particularly limited as long as it is coated on the surface of the second mold and then cured to form a pattern and is releasable from the second mold. .

According to a second embodiment of the present disclosure, the step of preparing the polyelectrolyte membrane includes: preparing a first mold having a pattern of a relief portion and a relief portion; Forming a substrate having a pattern of embossed portions and embossed portions inverted with the first mold using the first mold; A second mold in which an inorganic oxide is relatively more deposited on the end portion of the relief portion of the substrate by depositing an inorganic oxide by tilting the patterned substrate in one direction and then tilting the inorganic oxide in a direction opposite to the one direction, ; Using the second mold to produce a third mold having a pattern of inverted engraved portions and embossed portions with the second mold; And fabricating a polymer electrolyte membrane having a pattern of an engraved portion and an embossed portion inverted from the third mold using the third mold.

As shown in FIG. 5, after forming the substrate 230 having the pattern of the engraved portion and the embossed portion inverted from the first mold using the first mold 100 having the pattern of the engraved portion and the embossed portion, A second mold 200 having a relatively larger amount of inorganic oxide deposited on the end portion of the relief portion of the substrate by depositing inorganic oxide by tilting the formed substrate in either direction and then tilting the inorganic oxide in a direction opposite to the one direction ) Can be produced. After the third mold 300 having the pattern of the engraved portion and the embossed portion inverted from the second mold is manufactured using the second mold 300, the third mold 300 is inverted with the third mold 300, A polymer electrolyte membrane having a pattern of engraved portions and embossed portions can be produced.

The first mold may be patterned on a surface of a silicon wiper or glass or the like. Specifically, the first mold may be patterned on one side of the silicon wiper.

The substrate is not particularly limited as long as it is applied onto the surface of the first mold on which the pattern is formed and then cured to form a pattern and is releasable from the first mold, but the substrate may be made of a siloxane polymer or a polyurethane polymer.

The inorganic oxide deposited on the substrate is not particularly limited, but may be, for example, SiO ₂ , Al ₂ O ₃ , and the like.

The inorganic oxide may be sputtered onto the substrate at an output of 25 W to 50 W for 10 minutes to 120 minutes. In this case, as shown in Fig. 5, relatively more inorganic oxide may be deposited on the end portion of the embossed portion of the substrate to form a thickening portion where the width of the embossed portion is increased.

The degree of tilting of the base material is not particularly limited as long as it is inclined from the ground, but the tilted angle of the base material can be 20 degrees or more and 60 degrees or less from the ground.

The third mold may be formed of a siloxane-based polymer or a polyurethane-based polymer, although the third mold is not particularly limited as long as it is coated on the surface of the second mold and then cured to form a pattern and is releasable from the second mold. .

According to a third embodiment of the present invention, the step of preparing the polymer electrolyte membrane includes: preparing a first mold having a pattern of a relief portion and a relief portion; Forming a substrate having a pattern of embossed portions and embossed portions inverted with the first mold using the first mold; Preparing a second mold by contacting the end of the embossed portion of the substrate with the curable resin composition to apply the curable resin composition only to the end of the embossed portion of the substrate; Using the second mold to produce a third mold having a pattern of inverted engraved portions and embossed portions with the second mold; And fabricating a polymer electrolyte membrane having a pattern of an engraved portion and an embossed portion inverted from the third mold using the third mold.

As shown in FIG. 6, the first mold 100 having the pattern of the engraved portion and the embossed portion may be used to form the substrate 230 having the pattern of the inverted embossed portion and the embossed portion inverted from the first mold. The second mold 200 can be manufactured by contacting the end of the embossed portion of the substrate with the surface of the curable resin composition layer 600 coated on the substrate to apply the curable resin composition only to the end of the embossed portion of the substrate. After the third mold 300 having the pattern of the engraved portion and the embossed portion inverted from the second mold is manufactured by using the second mold, the third mold 300 and the inverted engraved portion are formed by using the second mold, A polymer electrolyte membrane having a pattern of embossed portions can be produced.

The first mold may be patterned on a surface of a silicon wiper or glass or the like. Specifically, the first mold may be patterned on one side of the silicon wiper.

The substrate is not particularly limited as long as it is applied onto the surface of the first mold on which the pattern is formed and then cured to form a pattern and is releasable from the first mold, but the substrate may be made of a siloxane polymer or a polyurethane polymer.

The curable resin composition may include a precursor of a siloxane-based polymer, and the solid content of the curable resin composition may be 3 wt% or more and 70 wt% or less based on the total weight of the curable resin composition.

The third mold may be formed of a siloxane-based polymer or a polyurethane-based polymer, although the third mold is not particularly limited as long as it is coated on the surface of the second mold and then cured to form a pattern and is releasable from the second mold. .

Hereinafter, the present invention will be described in more detail by way of examples. However, the following embodiments are for illustrative purposes only and are not intended to limit the specification.

[Example]

[Example 1]

Preparing a silicone wiper as a first mold having a pattern of a relief portion and a relief portion, applying a composition including a polyurethane polymer on the first mold, and forming a polyurethane substrate having a pattern of a relief portion and a relief portion inverted from the first mold . The pattern is formed by sputtering SiO ₂ or Al ₂ O ₃ on the surface of the base material was produced in the distal end of the boss portion described inorganic oxide is relatively more depositing a second mold.

An image of a scanning electron microscope (SEM) observing a cross section of a second mold on which an inorganic oxide is deposited is shown in Fig.

A third mold having a pattern of engraved and embossed portions inverted with the second mold was prepared using a composition comprising a precursor of polydimethylsiloxane (PDMS) on the second mold. A composition containing sulfonated poly (arylene ether sulfone) (SPAES) was applied on a third mold to prepare a polymer electrolyte membrane having inverted engraved and embossed patterns.

 [Example 2]

Preparing a silicone wiper as a first mold having a pattern of a relief portion and a relief portion, applying a composition including a polyurethane polymer on the first mold, and forming a polyurethane substrate having a pattern of a relief portion and a relief portion inverted from the first mold . A slide glass is placed on one side of the patterned substrate, and SiO ₂ or Al ₂ O ₃ is deposited at an angle of 45 ° with respect to the surface of the substrate. Thereafter, the slide glass is placed on the other side of the substrate and the SiO ₂ or Al ₂ O ₃ is re- A second mold was prepared.

An image of a scanning electron microscope (SEM) observing a cross section of a second mold having an inorganic oxide deposited thereon is shown in Fig.

A third mold having a pattern of engraved and embossed portions inverted with the second mold was prepared using a composition comprising a precursor of polydimethylsiloxane (PDMS) on the second mold. A composition containing sulfonated poly (arylene ether sulfone) (SPAES) was applied on a third mold to prepare a polymer electrolyte membrane having inverted engraved and embossed patterns.

[Example 3]

Preparing a silicone wiper as a first mold having a pattern of a relief portion and a relief portion, applying a composition including a polyurethane polymer on the first mold, and forming a polyurethane substrate having a pattern of a relief portion and a relief portion inverted from the first mold .

A composition comprising a precursor of polydimethylsiloxane (PDMS) (polydimethylsiloxane precursor: crosslinking agent weight ratio = 90: 10) was spin-coated on the substrate for 30 minutes to form a curable curable resin composition layer.

The end of the embossed portion of the polyurethane base was brought into contact with the curable resin composition layer to prepare a second mold. At this time, the depth of the end of the embossed portion contacting the curable resin composition layer may be 50% or less of the length of the embossed portion.

A third mold having a pattern of engraved and embossed portions inverted with the second mold was prepared using a composition comprising a precursor of polydimethylsiloxane (PDMS) on the second mold. A composition containing sulfonated poly (arylene ether sulfone) (SPAES) was applied on a third mold to prepare a polymer electrolyte membrane having inverted engraved and embossed patterns.

[Comparative Example 1]

SPAES 1 g of sulfonated poly (arylene ether sulfone) (SPAES) was dissolved in 9 g of N, N-dimethyl acetamide (DMAc) as a solvent, and an electrolyte membrane without a projection was prepared by casting method using a 300 μm doctor blade did.

[Comparative Example 2]

A composition (polydimethylsiloxane precursor: crosslinker weight ratio = 90: 10) comprising a polydimethylsiloxane (PDMS) precursor on a first mold was prepared as a first mold with a pattern of engraved and embossed portions, Was coated with the solution by spin coating or casting, dried in a vacuum oven at 60 캜 for 12 hours, and then separated from the first mold to prepare a second mold. A solution of 1 g of sulfonated poly (arylene ether sulfone) (SPAES) as a solvent in 9 g of N, N-dimethyl acetamide (DMAc) was applied on the second mold by spin coating or casting method, To prepare a polymer electrolyte membrane having a constant width after drying for 12 hours.

FIG. 7 shows an image of a scanning electron microscope (SEM) observing a polymer electrolyte membrane provided with protrusions having a constant width.

10: electrolyte membrane
20, 21: catalyst layer
30, 31: gas diffusion layer
50: cathode
51: anode
60: Stack
70: oxidant supplier
80: fuel supply unit
81: Fuel tank
82: Pump
100: First mold
200: second mold 230: substrate
250: inorganic oxide
300: third mold
400: electrolyte membrane
500: Projection 530:
560: width reduction portion
580: Groove
600: Curable resin composition layer

Claims (14)

A polymer electrolyte membrane having a plurality of protrusions on its surface;
An anode catalyst layer provided on one surface of the polymer electrolyte membrane; And
And a cathode catalyst layer provided on the other surface of the polymer electrolyte membrane,
Wherein the protrusions are provided with a thickening portion in which the width of the protrusions increases inward from an inside of the protrusions in contact with the polymer electrolyte membrane and protruding from the protrusions. The membrane electrode assembly of claim 1, wherein the protrusions are provided with a width decreasing portion whose width decreases from the inside of the projection in contact with the polyelectrolyte membrane to the outward direction in which the protrusions protrude. The membrane electrode assembly according to claim 2, wherein the protruding portion and the width reducing portion of the protrusion are provided continuously from the inside of the projection in contact with the polymer electrolyte membrane to the outward protruding direction of the protrusion. The membrane-electrode assembly according to claim 1, wherein the anode catalyst layer and the cathode catalyst layer are provided on ends of the projections, filling a space between projections of the polymer electrolyte membrane. The membrane electrode assembly according to claim 1, wherein the projections are columnar or line-shaped. The membrane-electrode assembly according to claim 1, wherein the height of the protrusions is 1 탆 or more and 100 탆 or less. The membrane-electrode assembly according to claim 1, wherein a distance between any one of the plurality of projections and one of the projections and the adjacent projections is not less than 1 占 퐉 and not more than 100 占 퐉. The membrane electrode assembly according to claim 1, wherein the width of the protrusions is 1 탆 or more and 100 탆 or less. The membrane electrode assembly according to claim 1, wherein the difference between the longest width of the enlarged portion and the width of the inside of the protrusion is 10 nm or more and 50 μm or less. A fuel cell comprising the membrane electrode assembly of any one of claims 1 to 9. Preparing a polyelectrolyte membrane having a plurality of projections on its surface;
Forming an anode catalyst layer on one side of the polymer electrolyte membrane; And
And forming a cathode catalyst layer on the other surface of the polymer electrolyte membrane,
Wherein the protrusions are provided with an enlarged portion in which a width of the protrusions increases from an inner side where the protrusions are in contact with the polymer electrolyte membrane to an outward direction in which the protrusions are protruded. [12] The method of claim 11, wherein preparing the polyelectrolyte membrane comprises: preparing a first mold having a pattern of a relief portion and a relief portion; Forming a substrate having a pattern of embossed portions and embossed portions inverted with the first mold using the first mold; Sputtering an inorganic oxide on the surface of the patterned substrate to produce a second mold; Using the second mold to produce a third mold having a pattern of inverted engraved portions and embossed portions with the second mold; And fabricating a polymer electrolyte membrane having a pattern of an engraved portion and an embossed portion inverted with the third mold using the third mold. [12] The method of claim 11, wherein preparing the polyelectrolyte membrane comprises: preparing a first mold having a pattern of a relief portion and a relief portion; Forming a substrate having a pattern of embossed portions and embossed portions inverted with the first mold using the first mold; Preparing a second mold having inorganic oxide deposited thereon by tilting the patterned substrate in one direction to form an inorganic oxide, and then tilting the organic oxide in a direction opposite to the one direction; Using the second mold to produce a third mold having a pattern of inverted engraved portions and embossed portions with the second mold; And fabricating a polymer electrolyte membrane having a pattern of an engraved portion and an embossed portion inverted with the third mold using the third mold. [12] The method of claim 11, wherein preparing the polyelectrolyte membrane comprises: preparing a first mold having a pattern of a relief portion and a relief portion; Forming a substrate having a pattern of embossed portions and embossed portions inverted with the first mold using the first mold; Preparing a second mold by contacting the end of the embossed portion of the substrate with the curable resin composition to apply the curable resin composition only to the end of the embossed portion of the substrate; Using the second mold to produce a third mold having a pattern of inverted engraved portions and embossed portions with the second mold; And fabricating a polymer electrolyte membrane having a pattern of an engraved portion and an embossed portion inverted with the third mold using the third mold.

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