WO1991014021A1

WO1991014021A1 - Sheet electrode material containing ion exchange resin, composite material thereof, and production thereof

Info

Publication number: WO1991014021A1
Application number: PCT/JP1990/000327
Authority: WO
Inventors: Hiroshi Kato; Eiichi Torikai
Original assignee: Japan Gore-Tex Inc.
Priority date: 1990-03-13
Filing date: 1990-03-13
Publication date: 1991-09-19

Abstract

This invention relates to a sheet electrode material containing an ion exchange resin, which is composed of: a base sheet having a number of interconnected pores and containing a binder comprising a fluoropolymer and a powdery, electrochemically functioning material dispersed therein, and a material containing an ion exchange resin, comprising an ion exchange resin alone or a mixture thereof with a metal. Said material containing an ion exchange resin is continuously distributed into the aforementioned pores through the surface of the base sheet.

Description

Specification Sheet electrode material containing ion exchange resin,

. The composite material and its manufacturing method

The present invention relates to a sheet-like electrode material containing ion-exchange resin, a composite material thereof, and a method for producing the same. More specifically, the present invention relates to a sheet-like electrode material containing an exchange resin having a three-dimensional electrochemical reaction surface and high mechanical strength, a composite material thereof, and a production method thereof. Background art

Generally, an electrochemical reaction in an electrochemical cell occurs at an interface between an electrode and an electrolyte. Therefore, the current-voltage characteristics of the electrochemical cell largely depend on the contact area between the electrode and the electrolyte. Is done. In particular, in the case of an electrolysis method using an ion-exchange resin membrane as a solid electrolyte, there is a problem that the contact area between the electrode and the electrolyte is much smaller than in the case of the aqueous solution electrolysis method. ing.

JP-A-55-38934 discloses an electrode material comprising an ion-exchange resin membrane and an electrode catalyst metal layer formed on one surface thereof by an electroless plating method. Since the contact between the electrode and the electrolyte is two-dimensional (planar), a further increase in the contact area between the two was desired. Japanese Patent Application Laid-Open Nos. 61-67786, 61-67788, 61-67790, and 61-87887 include, for example, an electrode on one or both sides of an ion-exchange resin membrane based on perfluorocarbon resin. An electrode material or the like in which a resin layer containing a catalyst powder and an ion exchange resin is combined is disclosed. However, in these electrode materials, the ion-exchange resin powder is distributed over the entire electrode material, and the ion-exchange resin is hydrophilic. It will be easy to rub. When a gas diffusion electrode such as a fuel cell and an oxygen separator is formed from such a hydrophilic electrode material, the electrode surface is easily wetted, which hinders the gas supply to the device and degrades the performance. -Comes up.

In order to solve such inconveniences, JP-A-61-67787 and JP-A-61-67789 disclose a hydrophobic resin containing no ion-exchange resin outside the ion-exchange resin-containing electrode material. For example, the force that proposes laminating a coating layer made of perfluorocarbon resin as a matrix; such an electrode material has a complicated structure and is expensive. There are drawbacks such as.

Further, in the above-mentioned electrode material, since the ion-exchange resin powder is dispersed in the electrode material, the contact between the ion-exchange resin powder and the ion-exchange resin powder is not sufficient, so that the hydrogen ion

The movement of (H ⁺ ;) becomes insufficient, causing a problem that the effect of the electrode is low. In order to solve such problems, it is necessary to further increase the mixing ratio of the ion-exchange resin powder. However, in this case, naturally, the obtained electrode material has higher hydrophilicity. In addition to the disadvantage that the electrode catalyst is covered with the ion-exchange resin, in some cases, such an inconvenience may occur that the catalytic action cannot be exhibited.

JP-A Nos. 61-2955387 and 61-295388 disclose an electrode material comprising an ion-exchange resin film and a thin film layer of a mixture of an ion-exchange resin and an electrode metal formed on one or both surfaces thereof. Has been done. However, in these electrode materials, it is necessary to use an organic solvent or a mixed solvent of an organic solvent and water for forming the thin film layer, and the ion exchange resin membrane swells remarkably by this solvent, If this is dried, it shrinks violently, and this film has the disadvantage of causing cracks.In addition, considerable heating is required for strong bonding of the ion-exchange resin film to the ion-exchange resin-metal mixture thin film. Pressurization is required, and the resulting electrode material is crushed, and the effective electrode-electrolyte interface contact area is considerably reduced. Since it does not have self-holding properties or has very low self-holding properties, it is necessary to apply considerable heat and pressure to join it to the ion exchange resin membrane. Often damage the Ion exchange 榭脂 film, has occurred or degrade the performance of the resulting electrode material, or the like to disable problem. Disclosure of the invention

Therefore, an object of the present invention is to provide an effective contact area between an electrolyte and an electrode. A sheet-like electrode material containing ion exchange resin, a composite thereof, which can be effectively used as a gas diffusion electrode, and can be easily manufactured without damaging the electrolyte membrane; and It is to provide a manufacturing method thereof.

Other objects and advantages of the present invention will be apparent from the following description.

According to the present invention, a sheet-like substrate comprising a binder made of a fluorine-containing polymer and an electrochemically functional material powder dispersed therein, and having a large number of continuous pores And an ion-exchange resin-containing material consisting of an ion-exchange resin alone or a mixture of an ion-exchange resin and a metal. A sheet-like electrode material containing ion-exchange resin, which is continuously distributed in the continuous pores from one surface of the base, is provided.

According to the present invention, a sheet-like substrate having a large number of continuous pores is formed from a mixture containing a binder made of a fluorine-containing polymer and a powder of an electrochemically functional material. One surface of the sheet-like substrate is brought into contact with an ion-exchange resin-containing solution, and this solution is permeated and impregnated from the one surface into the continuous pores of the sheet-like substrate. And thereby distributing the ion-exchange resin continuously from one surface of the sheet-like substrate into the continuous pores, thereby producing a sheet-like electrode material containing an ion-exchange resin. Provided.

According to the present invention, a mixture containing a binder made of a fluorine-containing polymer and a powder of an electrochemically functional material is further prepared from A sheet-like substrate having a number of continuous pores is formed, and one surface of the sheet-like substrate is brought into contact with a solution containing an ion-exchange resin and a metal compound. The impregnated body is infiltrated and impregnated into continuous pores of the substrate, subjected to a drying treatment, and further subjected to a reduction treatment for the metal compound, whereby the mixture of the ion-exchange resin and the metal is treated with the sheet. A method for producing a sheet-like electrode material containing an ion-exchange resin, comprising continuously distributing from one surface of a substrate in the continuous pores. BRIEF DESCRIPTION OF THE FIGURES

The invention will be better understood from the following description with reference to the accompanying drawings.

FIGS. 1, 2, 3, and 4 are graphs respectively showing current-voltage characteristics of an electrolytic device and a comparative electrolytic device obtained using the sheet-like electrode material of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

The sheet-shaped electrode material has a non-porous thin film formed of the ion-exchange resin-containing material on one surface of the sheet-shaped substrate, and the non-porous thin film formed on the other surface of the sheet-shaped substrate. It may be one in which the cation exchange resin-containing material is not substantially present.

Further, the above-mentioned sheet-like electrode material is obtained by binding the ion-exchange resin membrane layer with a perfluorocarbon-containing ion-exchange resin film layer on one surface on which the ion-exchange resin-containing material is distributed. Content sheet Electrode Z-perfluorocarbon-containing ion exchange resin membrane composite material may be formed.

The sheet-like substrate of the electrode material of the present invention is formed from a mixture of a binder made of a fluorine-containing polymer and an electrochemically functional material powder dispersed and bound therein.

Fluorine-containing polymer binders include, for example, polytetrafluoroethylene (PTFE), tetrafluoroethylene, fluoroalkylsilane copolymer (PFA), and tetrafluoroethylene. Styrene-hexafluoroethylene copolymer (FEP), trifluorene chloroethylene copolymer (CPTFE), and tetrafluoroethylene-ethylene copolymer (ETF) At least one kind selected from B) and the like is preferred, and particularly, PTFE is preferred.

The electrochemically functional material powder is, for example, carbon powder, for example, graphite, carbon black, and activated carbon powder, and at least one metal having a catalytic activity on these carbon powders, for example, platinum group metal. that allowed carrying, flour powder of metal having a catalytic function (eg platinum black, palladium black, etc.), metal oxides _{_{(eg, Ru0 2, I rQ 2,}} P b0 2 , etc.) are selected from such as powder Including one or more.

The blending ratio of the electrochemically functional material in the sheet-like substrate of the present invention to the powder and the fluorine-containing polymer binder varies depending on the use of the electrode material to be produced and the desired characteristics. The content of the fluorine-containing polymer binder is preferably 2 to 80 parts by weight based on 20 to 98 parts by weight of the chemically functional material powder. If the electrode material is required to be highly hydrophilic, increase the content of the electrochemically functional material powder.If the target electrode material is required to be hydrophobic, the content of the binder is increased. Should be raised. When the binder content is less than 2 parts by weight based on 100 parts by weight of the binder-functional material mixture, the mechanical strength of the obtained sheet-like substrate becomes insufficient, and when it is higher than 80 parts by weight. In addition, the electrochemical function of the obtained electrode material becomes unsatisfactory. Generally, it is preferred that the sheet-like substrate used in the present invention has a thickness of 50 to 400 layers.

In the electrode material of the present invention, the ion-exchange resin-containing material composed of the ion-exchange resin alone or a mixture of the ion-exchange resin and a metal, particularly a metal having a catalytic ability, is used as the sheet-like substrate. It is distributed continuously in continuous pores from one side. The distribution amount of the ion-exchange resin-containing material is from one surface of the sheet-like substrate to the other surface. The distribution may have a gradient. For example, the distribution amount may gradually increase from one surface side to the other surface side. It may be distributed so as to decrease.

The ion-exchange resin used in the electrode material of the present invention functions as a solid electrolyte, and includes, for example, a resin in which a fluorine-containing hydrocarbon is a main component of a main chain, and a cation-exchange group is bonded to the main chain. For example, it is preferable to use a copolymer of tetrafluoroethylene and sulfonylfluoride vinyl ether.

In addition, metals in the solid electrolyte-containing material, particularly metals having a catalytic activity, include, for example, platinum, iridium, palladium, and π-dimension. Preferably, it is of at least one species. The content of the metal in the material containing the exchange resin is generally 50% or less based on the weight of the ion exchange resin.

In the electrode material of the present invention, a non-porous thin film formed from an ion exchange resin-containing material is formed on one surface of the sheet-like substrate, and ion exchange is formed on the other surface of the sheet-like substrate. It is preferable that the resin-containing material is substantially absent, that is, it is not present at all, or even if present, in a very small amount.

The formation of such a nonporous ion-exchange resin-containing material layer is effective for improving the contact characteristics between the electrode material and the perfluoro-ion exchange resin as a solid electrolyte. In addition, the surface where the ion-exchange resin-containing material is not substantially present is used as a gas supply path and a liquid permeation path, and between the ion-exchange resin-containing material membrane and the power supply (power supply). It is effective as cushioning material.

The electrode material of the present invention may be formed into an electrode composite material by laminating and binding a perfluorohydrocarbon-containing ion-exchange resin film on one surface where the ion-exchange resin-containing material is distributed. Such a composite material has advantages such as reduced ohmic loss and improved handleability.

The method for producing a sheet-like electrode material containing an ion-exchange resin of the present invention has a large number of continuous pores from a mixture containing a binder comprising a fluorine-containing polymer and a powder of an electrochemically functional material. A sheet-like substrate is formed, and one surface of the sheet-like substrate is brought into contact with an ion-exchange resin-containing solution, and the solution is applied to the one surface. From the sheet-like substrate into the continuous pores by subjecting the impregnated body to a drying treatment. It is characterized by being continuously distributed and fixed.

Another method for producing a sheet-like electrode material containing an ion-exchange resin of the present invention is a method comprising the steps of: preparing a binder comprising a fluorine-containing polymer; and a mixture containing a powder of an electrochemically functional material. A sheet-like substrate having a large number of continuous pores is formed, and one surface of the sheet-like substrate is brought into contact with a solution containing an ion exchange resin and a metal compound. In a base material, the impregnated body is dried, the metal compound is reduced, and the mixture of the ion-exchange resin and the metal is mixed with the sheet. Characterized in that it is continuously distributed and fixed in the continuous pores from one surface of the substrate.

In the method of the present invention, the sheet-like substrate is produced by uniformly mixing a predetermined amount of the electrochemically functional material powder and a fluorine-containing polymer binder, and hot-pressing this mixture. I can do it. Alternatively, the above mixture was mixed with a liquid lubricant, or without mixing, in rolled to sheet one preparative shaped body good _t above sheet one preparative shaped substrate manufacturing method as the heating roll, sheet-like substrate in Many continuous pores are naturally formed between the particles of the electrochemically functional material powder.

The sheet-like substrate used in the present invention can be prepared by the method described in JP-B-63-19979 by using the above-mentioned electrochemically functional powder and the fluorine-containing polymer. A paste prepared by adding a liquid lubricant to a mixture with the coalescing binder may be roll-rolled or extruded to produce the paste. Such a sheet-like substrate has high functional strength and easy control of porosity and pore size, and is therefore suitable for the method of the present invention.

When the ion-exchange resin is made of only the ion-exchange resin, one surface of the sheet-like substrate is brought into contact with at least one solution of the ion-exchange resin, and the continuous pores of the sheet-like substrate are exposed. Inside, the solution is permeated and impregnated from its contact surface, and the impregnated body thus obtained is dried. ΙϋBy the immersion treatment, the ion-exchange resin solution continuously permeates and diffuses from one surface of the sheet-like substrate into the continuous pores. At this time, the distribution amount of the solution in the continuous pores may be smaller as the distance from the one surface is larger ₍ that is, the amount of the ion-exchange resin solution impregnated in the continuous pores is a sheet-like substrate. It may be distributed with a decreasing concentration gradient from one surface (the surface in contact with the solution) to the other surface. If such an impregnated body is subjected to, for example, a drying treatment and, if necessary, a further heat treatment, it is solidified. The exchange resin is continuously distributed and fixed from one surface of the sheet-like substrate into the continuous pores, and at this time, the ion exchange resin is distributed from one surface of the sheet-like substrate to the other surface. May be distributed and fixed so that they change with a gradient.

When the ion-exchange resin-containing material is composed of an ion-exchange resin and a metal, particularly an electrode catalyst metal, a sheet-like substrate having a large number of continuous pores is prepared in the same manner as described above, and the sheet-like substrate is formed. Of at least one ion exchange resin and at least one The solution is brought into contact with a solution containing a metal compound, and the solution is continuously infiltrated and infiltrated into continuous pores from one surface of the sheet-like substrate. Next, the impregnated body thus obtained is dried, for example, at a temperature of 50 to 90 ° C, and if necessary, further heat-treated at a temperature of 110 to 170 ° C. Next, the dried metal compound in the ion-exchange resin-metal compound mixture is subjected to a reduction treatment to reduce the metal compound to a metal. Through these treatments, the ion-exchange resin-containing material is continuously distributed and fixed from one surface of the sheet-like substrate into the continuous pores. Of course, the distribution amount of the ion-exchange resin-containing material in the continuous pores may have a gradient from one surface of the sheet-like substrate to the other surface. In the method of the present invention, the ion exchange resin solution is prepared by dissolving the ion exchange resin in a solvent such as ethanol or a mixed solvent of ethanol and water. The ion exchange resin concentration of this solution is not particularly limited as long as this solution can penetrate into the sheet-like substrate, but is generally used in the range of 0.5 to 20% by weight. The metal compound used in the method of the present invention is a compound which can be reduced to a corresponding metal, and is selected from, for example, penta-methyl pentamine platinum and penta-methyl pentamine palladium.

Generally, the metal compound is used so that the metal obtained by reduction is 5 to 50% based on the weight of the ion exchange resin. Hydrogen, sodium borohydride, hydrazine and the like are used as a reducing agent for the reduction of metal compounds, and the reduction treatment is generally performed at a temperature of 15 to 180 ° C. To permeate and impregnate the ion exchange resin solution or the ion exchange resin-metal compound mixture solution into the sheet-like substrate, a predetermined amount of this solution is added to the sheet-like substrate. The solution may be applied to the surface and allowed to penetrate into the continuous pores, or the solution may be sucked up into the continuous pores from one surface of the sheet-like substrate while applying a reduced pressure suction treatment to the opposite surface.

An ion exchange membrane may be bonded to the electrode material of the present invention, or the electrode material of the present invention may be adhered to a porous power feeder such as porous carbon or porous titanium, and this may be bonded to the ion exchange membrane. The electrode material of the present invention may be used by pressing against an exchange membrane, or may be used simply by pressing against the ion exchange membrane with a porous power supply. In order to bond the above-mentioned film bodies to each other, it is necessary to heat and bond at a temperature of 100 to 200 ° C. and a pressure of 1 to 200 kg Z cnf ©.

In the method of the present invention, the sheet-like substrate may be bonded to a power supply or a current collector (for example, a porous carbon material or a titanium material) and then subjected to an ion exchange resin impregnation treatment. Example

The present invention is further illustrated by the following examples, the scope of the present invention is not limited to these examples have needless to say ₀

Example 1

A mixture of 35 parts by weight of carbon black carrying 10% by weight of platinum, 15 parts by weight of FEP powder and 50 parts by weight of PT FE powder is mixed with 120 parts by weight of a liquid lubricant (Solvent Naphtha). A paste was prepared, and the paste was subjected to an extrusion and rolling process to obtain a 0.25 mm thick sheet-like molded product.

This sheet-like molded product is heated to 200 ° C and the porosity is 85%. A sheet-like substrate was prepared.

A 5% strength perfluoro σ sulfonate resin solution was diluted with ethanol to prepare a 3% strength by weight solution.

On one surface of the sheet-like substrate, the above-mentioned perfluorosulfonic acid resin solution is applied in a coating amount of 20 m £ Zm ² , and the solution is applied from the solution application surface of the sheet-like substrate to its internal continuous pores. The electrode sheet was prepared by impregnating the inside and drying the obtained soaked body at 120 ° C. The surface of the solution-coated side of this electrode sheet has a contact angle of 90 degrees with water droplets, so that even if the electrode sheet gets wet and the electrode sheet surface is vertical, the water that wets the surface flows down. Did not. However, on the opposite side of the electrode sheet, water droplets were moving freely in a granular manner, ie, the opposite side was not wetted by water. From this, it was confirmed that one surface of the electrode sheet was covered with a thin layer of resin-exchange resin, but no ion-exchange resin was exposed on the other surface.

The above electrode sheet was used as a force source, and an ion exchange resin membrane (trade name: Nafion # 117, made by DuPont, thickness: ◦.2) with platinum plating on one side The above-mentioned platinum-plated surface is used as a node, and an expanded titanium film provided with a platinum-plated plate is used as a current-collecting rest, and the ion-exchange thin resin layer of the electrode sheet is used. Then, the electrolytic device was pressed against the ion exchange resin with the current collector.

Pure water was supplied to the anode side of this electrolyzer, and air was supplied to the power source side to form an oxygen generator. The current-voltage characteristics of this electrolytic device were measured, and the results are shown in FIG. Also, on In the electrolysis apparatus, the electrode sheet and the ion-exchange resin membrane were heated and pressurized at 170 ° C. and 6 kg Z crf to join them. The obtained electrolytic device exhibited the same characteristics as those described above.

Comparative Example 1

The same operation as in Example 1 was performed. However, instead of the electrode sheet described in Example 1, a sheet composed of 40 parts by weight of platinum black powder and 60 parts by weight of PTFE was used.

FIG. 1 shows current-voltage characteristics of the obtained electrolytic device.

Comparative Example 2

The same operation as in Example 1 was performed. However, the sheet-like substrate was used as an electrode sheet without performing an ion-exchange resin impregnation thereon. -Fig. 1 shows the current-voltage characteristics of the obtained electrolytic device.

Example 2

The same operation as in Example 1 was performed. However, as an impregnating solution for the sheet-like body, an alcohol solution of perfluorosulfonate resin (naphine) and an aqueous solution of platinum at the mouth of platinum (platinum) are used. Concentration: 2 mg Z m) was used, and a solution with an ion exchange resin concentration of 3% by weight and a platinum concentration of ϋ.5% by weight was used. A hydrogen reduction treatment was performed at a temperature of ° C to reduce the platinum-ammine complex to platinum.

Example 3

From a mixture of 75 parts by weight of carbon black, 10 parts by weight of FEP and 15 parts by weight of PT FE, the thickness of 150 parts A conductive and porous sheet-like substrate having a porosity of 80% was prepared.

Separately, a mixed solution of 10 / ^ of an ethanol solution containing 3% by weight of ion-exchange resin and 3 ml of an aqueous solution of pentaammonium platinum chloride containing 2% by weight of platinum was prepared. .

-This mixed solution was applied to one surface of the sheet-like substrate at a coating amount of 20 mZrf, the other surface was subjected to a reduced pressure treatment, and the mixed solution was sucked and impregnated into continuous pores of the sheet-like substrate. The solution was further applied to the coated surface of the impregnated body at a coating amount of 20 mZrr to form a surface layer.

-1

The impregnated body was dried at 50 ° C. and dried at 50 ° C., and heated to 120 ° C. in a stream of hydrogen to reduce the platinum compound to platinum.

The obtained electrode sheet was used as a force source, which was brought into close contact with a 200-thick ion exchange resin membrane (trade name: Nafion # 117 ', manufactured by Dupont), and used as an end node. An electrolyzer was assembled by using a platinum exchange resin film of 4 mg Z cnf applied to a metal exchange resin membrane by an electroless plating method.

Hydrolysis was performed using this electrolytic device. Fig. 2 shows the current-voltage characteristics of this analyzer.

Comparative Example 3

Electrolysis equipment obtained by applying 4 mg Zcnf platinum plating by electroless plating on both sides of an ion exchange resin membrane (trademark: Nafion # 117, manufactured by DuPont, thickness of 200 lords) , And the same water electrolysis as in Example 3 was performed. Fig. 2 shows the current-voltage characteristics of this electrolytic device. Example 4

Creating Complex A

A coagglomeration mixture consisting of 95 parts by weight of lead dioxide (PbQ _2. Average particle size: 5), 1 part by weight of FEP and 4 parts by weight of PTFE was prepared by a coagulation method, and extruded and rolled to a thickness of 50 parts. A porous sheet-like substrate containing Sir's PbOs was prepared.

On one surface of the sheet-like substrate, a 5% by weight solution of an ion exchange resin (solvent: ethanol) was applied in a coating amount of 20 Zm ', and treated in the same manner as in Example 1 to form an electrode sheet. Created.

The electrode sheet is laminated with its coated surface facing ion exchange resin II (trademark: Nafion # 117), and heated and pressurized to 70 kg Xcnf at 80 ° C to join them together to form a composite. Body A.

Creating Complex B

Carbon that carries 10% by weight of platinum by co-agglomeration. A co-coagulant mixture consisting of 35 parts by weight of black, 20 parts by weight of FEP and 45 parts by weight of PTFE is prepared. A porous sheet-like substrate with a thickness of 130 mm was prepared by the rolling method.

This sheet-like substrate was bonded to a multilayer SUS mesh (surface layer: 65 mesh), which had been subjected to a water-repellent treatment with a fluororesin, by applying heat and pressure at 350 and 1 kgZcrf. The same ion-exchange resin mixed solution of pentaammine-platinum and pentaammonium as described in the Example was applied to the surface of the sheet-like substrate of this bonded body with an application amount of, and the SUS mesh side of the bonded body was applied. Then, the mixed solution was suction-impregnated into the continuous pores of the sheet-like substrate. Further, the mixed solution was applied to the surface of the sheet-like substrate at an application amount of 20 m £ Zm ² , The impregnated joined body was dried at 50: C, and subjected to a hydrogen reduction treatment at 120 ° C to precipitate platinum. Complex B was obtained.

Creation of electrolysis equipment

The Pb0 ₂ containing electrode sheet of composite A and Ryono over de were assembled electrolysis device electrodes sheets of composite B as a force source de.

Pure water was supplied to the anode side of this electrolyzer, and air was supplied to the cathode side to perform electrolysis.

Figure 3 shows the current-voltage characteristics at this time. Oxygen containing about 13% ozone was obtained from the anode side by the above electrolytic operation, but no hydrogen was generated on the power source side.

Comparative Example 4

The same operation as in Example 4 was performed. However, the composite solutions I and B were not impregnated with the ion exchange resin-containing solution.

Fig. 3 shows the current-voltage characteristics of the obtained electrolytic device.

卖 Example 5

A co-agglomeration mixture consisting of 40 parts by weight of carbon black supporting 10% by weight of platinum, 20 parts by weight of FBP, and 40 parts by weight of PTFE was prepared by the co-agglomeration method, and the mixture was deposited and rolled to a thickness of 200 mm A porous sheet-like substrate was prepared.

The sheet-like substrate was bonded to a pressure-sensitive paper whose surface was treated with a fluororesin by a water-repellent treatment under the conditions of 355 ° C. and 1 kgZcnf.

On the surface of the sheet-like substrate of the composite obtained in this manner, the same ion-exchange resin as that described in Example 2 was used. The mixed platinum solution was applied at a coating amount of 20 m £ Zn, and the mixed solution was suctioned and impregnated into the continuous pores of the sheet-like substrate under reduced pressure from the pressure vessel side of the composite. . The impregnated composite was dried at 50 ° C., and subjected to hydrogen reduction at 120 ° C. to deposit platinum to prepare a composite electrode sheet.

Two composite electrode sheets are laminated so that the bonbon paper is placed outside, and an ion exchange resin membrane (trademark: Nafion # 117, 200 Sir) is inserted between both layers. The three were integrated by heating and pressing at 170 ° C. and 3 kg Zcnf.

The obtained hydrogen gas was supplied to one side of the electrolyzer and air was supplied to the other side of the electrolyzer to form an SPE type fuel cell, which was operated. Fig. 4 shows the current-voltage characteristics at this time.

The electrode material of the present invention has the following characteristics.

1. Since the ion exchange resin is continuously distributed and fixed in the continuous pores of the sheet-like substrate, a continuous contact surface between the electrode and the solution f is formed three-dimensionally. Since the movement of hydrogen ion (H) proceeds smoothly, the electrochemical reaction is performed efficiently.

2. The impregnation amount and distribution of the ion exchange resin in the sheet-like substrate can be set and manufactured as desired. ·

3. One surface of the electrode material can be made hydrophobic without ion exchange resin and used for gas diffusion electrodes such as fuel cells and oxygen separators.

4. Cover one side of the electrode material with an ion exchange resin layer It can be used for applications such as water electrolysis, salt electrolysis, and hydrochloric acid electrolysis.

5. By using a high-strength membrane (for example, one made by the method of JP-B-63-19979) as a sheet-like substrate, it can be simply brought into contact with the ion-exchange resin membrane or the power supply without joining it. And sufficient self-support is obtained.

6. There is no need to form an electrode on the ion exchange membrane, so there is no damage to the electrode material.

7. Even when heated and pressed against the ion-exchange membrane, the three-dimensional reaction interface area in the electrode material hardly decreases.

8. Since the three-dimensional reaction interface is formed in the conductive sheet-like substrate, the efficiency of power supply (eg, in oxygen separators and water electrolyzers) and current collection (eg, in fuel cells) are extremely low. High This effect is particularly enhanced by distributing the mixture of the ion exchange resin and the metal in the continuous pores of the sheet-like substrate.

9. Since the sheet-like substrate does not swell with the solvent, the step of impregnating the ion-exchange resin-containing solution is easy, and a high-performance electrode material can be obtained efficiently.

Claims

^ Range of request

1. a sheet-like substrate comprising a binder made of a fluorine-containing polymer and an electrochemically functional material powder dispersed therein, and having a large number of continuous pores;

A material containing an ion-exchange resin alone or a mixture of an ion-exchange resin and a metal;

Composed of

An ion-exchange resin-containing sheet-like electrode material, wherein the ion-exchange resin-containing material is continuously distributed in the continuous pores from the sheet-like substrate.

2. The sheet according to claim 1, wherein the ion-exchange resin-containing material forms a non-porous thin film on one surface of the sheet-like substrate, and is substantially absent on the other surface. Electrode material,

3. An ion-exchange resin-containing electrode sheet material as set forth in claim 1 or 2 above, comprising a sheet-like electrode material and an ion-exchange resin film layer containing perfluorocarbon hydrocarbons. Are bonded on one surface of the sheet-like electrode material where the ion-exchange resin-containing material is distributed, wherein the ion-exchange resin-containing sheet-like electrode composite material is bonded.

4. From a mixture containing a binder made of a fluorine-containing polymer and a powder of an electrochemically functional material, a sheet-like substrate having a large number of continuous pores is formed. Contacting with a solution containing a heat-exchange resin to infiltrate and impregnate the solution into the continuous pores of the sheet-like substrate from the one side, and subject the impregnated body to a drying treatment, whereby the ion-exchange is performed. Before the resin A method for producing an ion-exchange resin-containing sheet-like electrode material, comprising: continuously distributing from one surface of the sheet-like substrate into the continuous pores. -

5. From a mixture containing a binder comprising a fluorine-containing polymer and a powder of an electrochemically functional material, a sheet-like substrate having a large number of continuous pores is formed, and one surface of the sheet-like substrate is formed. A solution containing an ion-exchange resin and a metal compound, and the solution is permeated and impregnated from the one surface into the continuous pores of the sheet-like substrate, and the impregnated body is subjected to a drying treatment. Performing a reduction treatment on the metal compound, whereby the mixture of the ion-exchange resin and the metal is continuously distributed from one surface of the sheet-like substrate into the continuous pores. A method for producing an exchange resin-containing sheet electrode material.