JPS62226583A - Electrode-matrix combined body of fuel cell and its manufacture - Google Patents

Abstract

PURPOSE:To increase a balance of wettability such as water repellent ability and hydrophlic nature to electrolyte within a catalyst layer by arranging two or more catalyst layers in which the amount of water repellent agent and pore forming agent are decreased in order, and a matrix layer comprising matrix material powder and a binder, or two or more matrix layers in which the amount of the binder is increased in order formed on the surface of the catalyst layer. CONSTITUTION:An electrode-matrix combined body consists of two or more catalyst layers, comprising catalyst powder, water repellent agent, and pore forming agent, in which the amount of the water repellent agent and the pore forming agents are decreased in order formed on the surface of an electrode substrate 10, and matrix layer comprising matrix material powder and a binder, or two or more matrix layers 12 in which the amount of the binder is increased in order formed on the surface of the catalyst layer 11. Since multilayers of the catalyst layer and the matrix layer are formed on the surface of the electrode substrate, a balance of wettability such as water repellent ability and hydrophilic nature to electrolyte such as phosphoric acid within the catalyst layer is increased, and the matrix layer having good permeability of electrolyte and good bonding ability to the catalyst layer can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrode/matrix assembly for a matrix fuel cell using, for example, phosphoric acid as an electrolyte, and a method for manufacturing the same.

[Conventional technology]

Figure 4 is 1, for example, Tokkai Sho! t-11. ! This is a process diagram of the conventional fuel cell electrode/IJ-lux combination production method shown in the CO5 publication. Preparation step (water repellent treatment step of applying water repellent treatment to the electrode base material obtained in step C),
, 7) is this water repellent treatment step (a coating step of applying the first catalyst layer as the first layer to the electrode base material treated in step 1), and (d) is the step of applying the first catalyst layer in this application step (3). A firing step of firing the applied electrode, (3) a step of applying a second first catalyst layer on the first catalyst layer, and (A) a step of applying a pore-forming agent such as bicarbonate in the second catalyst layer. A pore-forming agent removal step for removing ammonium, (7) a firing step for firing the electrode coated with the first catalyst layer, and (g) a matrix layer application step for applying a matrix material on the first catalyst layer. , (TE) is a firing process for firing the electrode/IJ sock combination obtained in this coating process.

An example of an electrode/IJ sock combination obtained through the above manufacturing process is shown in FIG. 5, for example. In the figure, (10) is an electrode base material, and (//) is a catalyst layer coated on the surface of this electrode base material (10).

(//a) is the first catalyst layer of this catalyst layer (//), (/ /b) IIi is also the first catalyst layer, (1
2) is a matrix layer coated on the surface of the catalyst layer (//). (/J) is catalyst powder that constitutes the catalyst layer (//).

(/ri) constitutes the catalyst layer (//) and is a water repellent agent that also serves as an adhesive, such as polytetrafluoroethylene7. (/!r) Matrix powder material constituting matrix layer (/, 2), (/6) I/'i Also matrix layer (12)
It is a binder that makes up the .

The conventional fuel cell electrode/ma) IJ sock assembly and its manufacturing method are configured as described above.

In the electrode base material preparation step (1), for example, a porous material (generally used such as carbon vapor) is prepared as the electrode base material (10), and a water-repellent binder such as polytetrafluoroethylene is applied to it. Coating and drying water repellent treatment process (
2), then the first catalyst layer (//a) coating step (
, 7), a mixture of the catalyst powder (/3) and the water repellent (/) is applied on the electrode base material (10) which has been subjected to water repellent treatment to form the first catalyst layer (//a). .

In the firing step (Ri 1), the electrode coated with the first catalyst layer (//a) is fired at a temperature of 300'C for 5 minutes.Next,
In the first catalyst layer coating step (sl), for example, 100 parts by weight of catalyst powder (/3) is applied onto the 11th!lI medium layer (//a) to form the first catalyst layer (//b). Then, in the step (6) of removing the pore-forming agent from the first catalyst layer (/lb), once
The pore-forming agent was removed by drying at 00°C, and the second catalyst layer (/
/b) After coating +7) Temperature 3
The electrode is fired at 10° C. to generate pores inside the first catalyst layer (//b). Next, the process of coating the matrix layer (12) (% fl A matrix layer (12) was formed by applying a mixture of (tetrafluoroethylene, etc.) (/6)tMikm so that a part of it also filled into the pores of the first catalyst layer (//b). The electrode/matrix assembly is fired in step 91 at a temperature of 300° C. for 5 minutes to complete the IJ sock assembly.

As is well known, this porcelain fuel cell is a device that has a matrix layer impregnated with an electrolyte between a fuel electrode and an air electrode, and can directly extract electrical energy through an electrochemical reaction.

[Problem that the invention seeks to solve]

When forming or replenishing the electrode/matrix of a fuel cell as described above, an electrolyte such as phosphoric acid is added to the matrix layer (1
2) is difficult to impregnate in the longitudinal direction, and the second catalyst layer (//
There was also a problem that the film could not be penetrated in the direction b), that is, the direction through which the matrix layer (/, 2) was penetrated. The cause of this is the firing process (wa) after coating the second catalyst layer (//b).
In order to fire the electrode at a high temperature of 350°C,
This is because the highly concentrated water repellent agent (/g) in the second catalyst layer (//b) gathers near the surface of the second catalyst layer (//b) to form a kind of water-repellent layer, and , Ma) IJ rack layer (
This is because the high concentration binder (/6) in 12) is, for example, polytetrafluoroethylene, which has very strong water repellency.

In addition, in the electrode/matrix assembly of the fuel cell as described above, in the coating process of the matrix layer (/2) (A'l or the baking process (re) after coating the matrix 7m (/, 2)), The matrix layer (/2) may peel off from the second catalyst layer (//b), or the matrix layer (/2) may peel off from the second catalyst layer (//b).
There was a problem that cracks were generated in the fuel cell (Y/Y), and the performance as a fuel cell (particularly pulp resistance) was deteriorated. The reason for this is similar to the above, and the second catalyst layer (//
In order to bake the electrode at a high temperature of vfn degree 3jθ°C in the baking step (7) after coating b), the second catalyst layer (//b
) Highly concentrated water repellent on the instep (Ha is the second)! l [11M layer (
//l:+) gather near the surface.

This is to form a kind of mold release 14. In addition, the electrode/matrix assembly of a fuel cell having the above structure and manufactured by the above method has a low utilization rate of the catalyst in the It coelectrode, and the electrolyte such as phosphoric acid is in the catalyst layer (// ) once permeated into the electrode base material (10), this problem was caused by part of the matrix layer (/2) filling the pores in the catalyst layer (//). It is because there is
In addition, since the catalyst layer (//) and matrix layer (12) are not multilayered, phosphoric acid, etc. in the catalyst layer (//)
This is because it is difficult to maintain the balance of wettability such as water repellency and hydrophilicity for solutes.

This invention was made in order to solve such problems, and includes a multilayer catalyst layer with different blending ratios of catalyst powder: water repellent: pore-forming agent, and a multilayer catalyst layer with different blending ratios of matrix powder material: binder. By adopting a combination with a multilayer matrix, it has good impregnation and permeability with electrolytes such as phosphoric acid, and has good adhesion with the catalyst layer.It has an IJ rack layer and has an IJ rack layer that prevents phosphoric acid, etc. in the catalyst layer. The purpose of the present invention is to obtain a fuel cell electrode ψ matrix assembly that has an improved balance of wettability such as water repellency and hydrophilicity with respect to the electrolyte.

Another object of the present invention, in addition to the above object, is to provide a method for manufacturing the electrode/matrix assembly of the above fuel cell.

[Means for solving problems]

The electrode/matrix assembly of the fuel cell according to the present invention is formed on the surface of an electrode base material and includes catalyst powder.

one or more catalyst layers comprising a water repellent agent and a pore-forming agent, in which the amounts of both the water repellent agent and the pore-forming agent decrease sequentially; and a matrix powder material and crystals formed on the surface of these catalyst layers. An electrode-matrix assembly for a fuel cell according to another invention of the present invention, which has seven matrix layers made of an adhesive or two or more matrix layers in which the amount of a binder is sequentially increased. The manufacturing method involves forming a multilayered media layer in which the amounts of a water repellent agent and a pore-forming agent are sequentially decreased on the surface of an electrode base material, and adding 7.
The method is to form an IJ rack layer or one or more layers in which the amount of bonded pairs increases sequentially, and to sinter the resulting electrode and IJ rack combination.

[For production]

In this invention, the multilayer catalyst layer and matrix layer as described above are formed on the surface of the electrode base material, so the balance of wettability such as water repellency and hydrophilicity for electrolytes such as phosphoric acid in the catalyst layer is maintained. A matrix layer with good electrolyte impregnation and permeability and good adhesion with the catalyst layer is formed.

Further, in another aspect of the present invention, the electrode/matrix assembly for a fuel cell as described above can be easily obtained.

〔Example〕

FIG. 1 is a process diagram showing one embodiment of the present invention. In FIG. 1, (C and (2) are completely the same as those in the conventional method, A coating/drying step in which one catalyst layer is applied and dried; (/8) is a coating/drying step in which a second catalyst layer is applied and dried on the first catalyst layer;
(/ri) is a coating/drying process in which the third catalyst layer is applied on top of the second catalyst layer and dried. Process, (2/
) is the coating/drying process of coating and drying the 2789722 layer on the first matrix layer, and (2) is the coating/drying process of coating and drying the 2789722 layer on the first matrix layer. second and third medium layers and first and second
Pre-firing step of pre-firing the electrode/matrix combination made by coating and drying the 789,722 layer (Part 3)
is the final firing process in which the pre-fired electrode/IJ sock assembly is fired.

Fig. 2 is a schematic cross-sectional view of the electrode/matrix assembly of the fuel cell manufactured by the manufacturing process shown in Fig. 1. In Fig. 1, (10'), (/J) to (/6) are It is exactly the same as in the electrode fist matrix combination.

(//) is the catalyst layer, the first catalyst layer (//ni'), the second catalyst layer
It consists of a catalyst layer (//B) and a third catalyst layer (//C), where (/λ) is a matrix layer and consists of a first matrix layer (/λA) and a 2789722 layer (12B).

In the electrode/matrix assembly of the fuel cell configured as described above, first, the electrode base material preparation step (c) uses a porous material (phosphoric acid resistant carbon vapor, etc.) as the electrode base material (10). A water repellent treatment step (2) is performed in which a water repellent binder such as polytetrafluoroethylene is applied and dried.Next, the first catalyst layer (
//A) In the coating-drying step (13), catalyst powder (/3'): water repellent (polytetrafluoroethylene, etc.) (HA) is applied onto the water-repellent electrode base material (/θ). :100 parts by weight of a pore-forming agent (ammonium hydrogen carbonate, etc.)
A mixture of parts by weight of UOO and parts by weight of H2o-to was applied and dried at a temperature of go to 10oC to form a catalyst layer (/
/A) Catalyst powder (/, 7): Water repellent (polytetrafluoroethylene, etc.) (C): 100 parts by weight of a pore-forming agent (ammonium hydrogen carbonate, etc.): 30 parts by weight: 10
Apply the mixture at a mixing ratio of -go parts by weight, and apply the mixture at a temperature of g
The first catalyst layer (//B) is formed by drying at 0 to 100°C. Next, the third catalyst layer (//C) is coated and dried (//
In Te), catalyst powder (
/J): Water repellent (polytetrafluoroethylene, etc.) (/
lI): Apply a mixture of pore-forming agent (ammonium hydrogen carbonate, etc.) at a mixing ratio of 100 parts by weight:/~po*basin:/~-0 parts by weight, and dry at a temperature of go~10oC. Third
Form a catalyst layer (//c). Next, in the first matrix layer coating/drying step (2□), the third catalyst layer (/
/C) on top of M) IJ sock powder material (average particle size 0
．． 6-7 μm silicon carbide, etc.) (/z): Binder (polytetrafluoroethylene, etc. with an average particle diameter of 7 μm) (/b)'It: 10° parts by weight: 061-2 parts by weight (preferably O , S to 7 parts by weight) is coated and dried at a temperature of 10 to 10[theta]C to form a first matrix layer (/CoA). Next, in the coating-drying process (co/) of the first matrix layer, the first matrix layer
A matrix powder material (silicon carbide, etc. with an average particle size of 0.6 to 1 μm) is placed on the IJx layer (12A).
(/j): Binder (average particle size/μIFL polytetrafluoroethylene, etc.) (/l)/00 weight fkm:
A mixture of /~j parts by weight (preferably Korg parts by weight) is coated and dried at a temperature of ~/00'C to form the 2789722nd layer (/co B). next,
In the preliminary formation step (-2), the entire electrode/matrix assembly produced as described above is preformed at a temperature of 150°C (preferably 200~2!; 0'C). do. Next, the final firing process (2J)
The entire pre-fired electrode/matrix combination is heated to a temperature of 310 to 3yoC (preferably 3JO to 14℃).
Final firing is performed at 0℃) to complete the electrode φ ma) IJ sock combination.

The electrode/matrix assembly of the fuel cell manufactured by the above manufacturing method is not fired until the 2789722nd layer (/8) is formed, and the second matrix layer (/λB) is
After forming, firing is performed.

In addition, the content of water repellent such as polytetrafluoroethylene (c) and binder (/6) in the third catalyst layer (//C) and the first matrix layer (/JA) is Since the water repellency is low, a water repellent layer is not formed on the bonding surface between the third catalyst layer (//C) and the first matrix layer (/, 2A), and the matrix layer (/2
) and in the direction of the third catalyst layer (//C), that is, in the direction through the matrix layer (/2), the impregnation-permeability of electrolyte such as phosphoric acid was the same as above.

Furthermore, the release layer as in the conventional type is no longer formed on the surface of the third catalyst;
12) The inconvenience of cracks occurring is eliminated.

In addition, in the catalyst layer (//) of the electrode/matrix combination manufactured by the above manufacturing method, the first catalyst layer (//A) contains 70 to 0% (preferably about 10%). ,
In the second catalyst layer (//B), ltj--g! r% (preferably about 70%), about tIj in the third catalyst layer (//C)
~tro% (preferably about 60%) voids are formed, and the content of water repellent such as polytetrafluoroethylene in the catalyst layer (//) is highest on the electrode base material (10) side. Since the matrix layer side (/2) is low, the catalyst layer (//) has strong water repellency on the electrode base material (10) side, and strong hydrophilicity on the matrix layer (/2) side, and therefore, It is now easier to maintain and adjust the balance of wettability such as water repellency and hydrophilicity for electrolytes such as phosphoric acid in the catalyst layer. As a result, the disadvantages of the conventional electrode/matrix IJ sock combination have been improved, and the fuel cell manufactured using the electrode/matrix assembly according to the present invention has a strong matrix layer and an electrolyte such as phosphoric acid. Since the impregnation and permeability are good and the wettability of the catalyst layer (//) is well balanced, the output voltage is high and the change over time is small, making it possible to improve the reliability of the fuel cell.

FIG. 3 is a process diagram showing another embodiment of this invention,
In the figure, (c, (ko l+ (/q) ~ (2o) is the first
It is exactly the same as in the figure. (2 da) is the first, second. and a pre-calcination step of pre-calcining the electrode/matrix combination on which the third catalyst layer and the first matrix layer have been applied and dried, txt) is the pre-calcined electrode/matrix)
A coating/drying step in which the IJ sock combination is applied by main firing and dried, and (27) is a final firing step in which the electrode/matrix combination is finally fired. A schematic cross-sectional view of the electrode/matrix combination obtained through these manufacturing steps is the same as that of the above embodiment, and is shown in FIG.

In the fuel cell electrode/matrix assembly configured as described above, the first. The second and third catalyst layers and the first matrix)
The matrix bonded body is subjected to the pre-firing step (2II) at a temperature of /! ;0~2g00G (preferably SOO~25
Preliminary firing is performed at 0℃). next.

In the main firing step (2), the electrode Φ matrix combination is heated at a temperature of 310-370'C (preferably 330-370'C).
Bake at AO0G). Next, in the second matrix layer coating/drying process (rolling), the first matrix layer (
A second matrix layer (12B) is coated on top of 12A) in exactly the same manner as the coating-drying step (co/) of FIG. 1 and dried. Next, in the final firing step (27), the electrode/matrix assembly coated with the second matrix layer (/coB) is heated to a temperature of 750 to 320°C (preferably 200°C to 200°C).
Final firing is performed at tO°C) to complete the electrode/matrix assembly.

The electrode/ma) IJ socks manufactured by the above manufacturing method are combined with the catalyst layer (//) and the IJ socks layer (1).
2k) at high temperature, and the second matrix layer (12k) is fired at high temperature.
Since B) is fired at a low temperature (melting temperature of polytetrafluoroethylene (327°C), which is a binder), the water repellency of the matrix layer (/IB) is weak, and the matrix layer (/IB) has weak water repellency, and the matrix layer (IJ) of an electrolyte such as sulfuric acid is The impregnation and permeability of the Tuxus layer (12) along the layer direction have been significantly improved, and electrolyte replenishment has been made easier. Of course, the matrix layer (/2) is strong in this case as well.
In addition, the impregnation and permeability of the electrolyte such as phosphoric acid in the direction through the matrix layer (12) is good, and the wettability of the catalyst layer (//) is well balanced, so the output voltage is high and the change over time is small. We were able to improve the reliability of fuel cells.

In addition, in the above example, polytetrafluoroethylene was used as the water repellent agent (c) of the catalyst layer (//) and the binder (/6) of the matrix layer (12), but it is not limited to this. Hexafluoropropylene-tetrafluoroethylene co]i combination.

At least one selected from fluorinated graphite and polytrifluoroethylene can also be used. Also.

The pore-forming agent for the catalyst layer (//) is not limited to ammonium hydrogen carbonate, but may also be used such as ammonium carboxymethyl cellulose or ammonium carbonate. Although we have explained the case of a body, it is also possible to use only an electrode without a matrix, and in this case, it is effective to maintain a better balance of wettability such as water repellency and hydrophilicity with respect to electrolytes such as phosphoric acid in the catalyst layer. . Furthermore, the electrolyte is not limited to phosphoric acid, and of course can be applied to alkaline solutions as well. Furthermore, in the electrode housing matrix combination, the number of catalyst layers is not limited to three, and the matrix layer is not limited to one layer, and even multiple catalyst layers and IJx layers may be used. can.

〔Effect of the invention〕

As explained above, this invention includes a porous electrode base material,
A catalyst powder is formed on the surface of the electrode base material.

a catalyst layer consisting of a water repellent agent and a pore-forming agent, in which the amounts of both the water repellent agent and the pore-forming agent decrease sequentially; a matrix powder material and a binder formed on the surface of the catalyst layer; or two or more matrix layers in which the amount of the binder increases sequentially,
A fuel cell that has a matrix layer that has good impregnation and permeability with electrolytes such as phosphoric acid and has good adhesion with the catalyst layer, and has an improved balance of wettability such as water repellency and hydrophilicity for the electrolyte in the catalyst layer. This has the effect of achieving IJ-lux integration. Furthermore, there is an effect that a fuel cell with high output voltage, small change over time, and high reliability can be obtained.

Another invention of the present invention includes a step of forming a first catalyst layer by applying and drying a mixture of a catalyst powder, a water repellent, and a pore-forming agent on the surface of a porous electrode base material; A mixture of a water repellent in a smaller amount than the first catalyst layer and a pore-forming agent in a smaller amount than the first catalyst layer is applied to the surface of the first catalyst layer and dried to form a second catalyst layer. A mixture of catalyst powder, a water repellent in a smaller amount than the second catalyst layer, and a pore-forming agent in a smaller amount than the second catalyst layer is coated on the surface of the second catalyst layer and dried. to form a third catalyst layer; and a step to form a first matrix layer by coating and drying a mixture of a gas trix powder material and a binder on the surface of the third catalyst layer formed in the above step. forming a second matrix layer by coating and drying a mixture of a matrix powder material and a binder in a relatively larger amount than the first matrix layer on the surface of the first matrix layer; Second. and a step of pre-calcining the electrode/matrix combination on which the third catalyst layer and the first and first matrix layers are formed, and a step of final firing of the pre-fired electrode/matrix combination. This has the advantage that a fuel cell electrode/matrix assembly such as the one shown in FIG.

[Brief explanation of drawings]

Fig. 1 is a process diagram showing one embodiment of the present invention, and Fig. 2 is a diagram showing the electrodes of a fuel cell manufactured by the process shown in Fig. 1.
FIG. 3 is a process diagram showing another embodiment of the present invention, FIG. FIG. 2 is a schematic cross-sectional view of an IJ-lux combination of electrodes and IJs of a fuel cell manufactured by the process shown in the figure. In the figure, (C is the preparation process, (, 2) is the water repellent treatment process, (/θ) is the electrode base material, (//) is the catalyst layer, (//A) is the first catalyst layer, (// B) is the second catalyst layer, (//C) is the third catalyst layer, (12) is the matrix layer, (/coro) is the first matrix layer, (72B) is the first matrix layer, (/3) is the Catalyst powder, (/ri) is water repellent, (/!] is ma) 17x powder material, (/a) is binder. (/ri), (7g), (/q), (20) I (2/),
(koro) is the coating and drying process, (ko2) and (:lg) are the preliminary forming process, (2, t) and (a7) are the final firing process,
(2S) is the main firing step. In each figure, the same reference numerals indicate four or equivalent parts.

Claims (14)

[Claims] (1) A porous electrode base material, which is formed on the surface of the electrode base material and includes a catalyst powder, a water repellent agent, and a pore-forming agent, and the amounts of both the water repellent agent and the pore-forming agent gradually decrease. Two or more catalyst layers and one matrix layer formed on the surface of the catalyst layer and consisting of a matrix powder material and a binder, or a matrix layer in which the amount of the binder increases sequentially 2
What is claimed is: 1. An electrode for a fuel cell, a matrix combination, characterized by having at least one matrix layer; (2) The electrode/matrix assembly for a fuel cell according to claim 1, wherein the catalyst layer is three layers and the matrix layer is two layers. (3) the catalyst layer is formed on the surface of the electrode base material and has a first catalyst layer having a relatively large intralayer pore diameter and relatively large water repellency; a second catalyst layer having a relatively smaller in-layer pore diameter and relatively smaller water repellency than the first catalyst layer; The matrix layer is formed of three layers including a third catalyst layer having an inner pore diameter and relatively small water repellency, and the matrix layer formed on the surface of the third catalyst layer does not fill the pores of the catalyst layer. Features Claim 1 or 2
An electrode/matrix combination for a fuel cell as described in . (4) The fuel according to claim 1, wherein the same material is used for the water repellent in the first to third catalyst layers and the binder in the first and second matrix layers. Battery electrode/matrix combination. (5) The water repellent in the first to third catalyst layers and the binder in the first and second matrix layers include polytetrafluoroethylene, hexafluoropropylene-tetrafluoroethylene copolymer, fluorinated graphite, and polytetrafluoroethylene. The electrode/matrix assembly for a fuel cell according to claim 1, wherein the electrode/matrix assembly for a fuel cell is at least one selected from the group consisting of trifluoroethylene. (6) The pore-forming agent in the first to third catalyst layers is at least one selected from the group consisting of ammonium carboxymethyl cellulose, ammonium carbonate, and ammonium hydrogen carbonate. An electrode/matrix combination for a fuel cell as described in . (7) The water repellent in the first to third catalyst layers is polytetrafluoroethylene, and the catalyst powder 1 in these catalyst layers
The parts by weight of the water repellent relative to 00 parts by weight are 150 to 400 parts by weight in the first catalyst layer, 30 to 200 parts by weight in the second catalyst layer, and 1 to 40 parts by weight in the third catalyst layer. An electrode/matrix assembly for a fuel cell according to claim 1 or 4. (8) The pore-forming agent in the first to third catalyst layers is ammonium hydrogen carbonate, and the weight part of the pore-forming agent based on 100 parts by weight of the catalyst powder in these catalyst layers is 20 to 20 parts by weight in the first catalyst layer.
80 parts by weight for the second catalyst layer, 10 to 50 parts by weight for the third catalyst layer, and 1 to 20 parts by weight for the third catalyst layer. (9) The porosity of the first to third catalyst layers is 70 to 90% in the first catalyst layer, 55 to 85% in the second catalyst layer, and 45 to 80% in the third catalyst layer. An electrode/matrix assembly for a fuel cell according to any one of claims 1 to 3. (10) The binder in the first and second matrix layers is polytetrafluoroethylene, the average particle size in these matrix layers is approximately 1 μm, and the binder is The weight part is
0.1 to 2 parts by weight in the first matrix layer and 1 to 5 parts by weight in the second matrix layer.
matrix conjugate. (11) forming a first catalyst layer by coating and drying a mixture of catalyst powder, water repellent, and pore-forming agent on the surface of the porous electrode base material; First, add a small amount of water repellent and
A step of forming a second catalyst layer by coating and drying a mixture of a pore-forming agent in a smaller amount than the catalyst layer on the surface of the first catalyst layer; Water repellent and second
A step of applying a mixture with a pore-forming agent in a relatively small amount than that of the catalyst layer on the surface of the second catalyst layer and drying it to form a third catalyst layer; and a step of applying the mixture of the matrix powder material and the binder to the above step. forming a first matrix layer by applying and drying the mixture on the surface of the third catalyst layer formed in the first matrix layer; A step of forming a second matrix layer by coating and drying on the surface of the layer, and preparing the electrode/matrix assembly in which the first, second, and third catalyst layers and the first and second matrix layers are formed. 1. A method for producing an electrode/matrix assembly for a fuel cell, comprising the steps of: firing the prefired electrode/matrix assembly; and final firing of the prefired electrode/matrix assembly. (12) Manufacture of an electrode/matrix assembly for a fuel cell according to claim 11, characterized in that preliminary firing is performed at a temperature of 150 to 280°C, and final firing is performed at a temperature of 310 to 370°C. Method. (13) Between the step of forming the first matrix layer and the step of forming the second matrix layer, the electrode/matrix combination in which the first, second, and third catalyst layers and the first matrix layer are formed is formed. Claim 11, comprising a step of pre-firing and a step of main-firing the pre-fired electrode/matrix combination, and finally firing the main-fired electrode/matrix combination. A method for producing an electrode/matrix assembly for a fuel cell as described in 1. (14) Preliminary firing is performed at a temperature of 150 to 280°C, main firing is performed at a temperature of 310 to 370°C, and final firing is performed at a temperature of 150 to 320°C. A method for producing an electrode/matrix combination for a fuel cell.