JP2006210135A - Catalyst electrode material, catalyst electrode, manufacturing method thereof, support material for electrode catalyst and electrochemical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst electrode material capable of furthering catalyst efficiency and of realizing high durability by eliminating dissolution of the support itself; to provide a catalyst electrode formed of the catalyst electrode material; to provide manufacturing methods for them; to provide a support material for forming the catalyst electrode material; and to provide an electrochemical device using the catalyst electrode. <P>SOLUTION: This support material for an electrode catalyst is mainly formed of an oxide such as titanium dioxide. This electrochemical device, in particular, a fuel cell is composed of a plurality of electrodes 5 and 7 and a proton conductor 3 sandwiched between the electrodes, wherein at least one of the plurality electrodes, in particular, an oxygen electrode 7 is formed of this catalyst electrode material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a catalyst electrode material, a catalyst electrode, a method for producing the same, a support material for an electrode catalyst, and an electrochemical device such as a fuel cell.

  A typical polymer electrolyte fuel cell has a pair of electrodes joined to both sides of a proton conductive solid polymer electrolyte membrane, and one electrode (fuel electrode) is made of pure hydrogen or reformed hydrogen gas or methanol. Alcohol is supplied as a fuel, and oxygen gas or air is supplied as an oxidant to the other electrode (oxygen electrode) to obtain an electromotive force. A fuel oxidation reaction is performed at the fuel electrode of the fuel cell, and oxygen is reduced at the oxygen electrode. Here, an ideal reaction formula when hydrogen is used as a fuel and an acidic electrolyte is used is expressed as follows.

Fuel (hydrogen, negative) electrode: H ₂ → 2H ⁺ + 2e ⁻
Oxygen (positive) electrode: O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O

FIG. 10 shows an example of the structure of such a fuel battery cell. The catalyst layer 1 in the figure may be mixed with an ion conductor, a water-repellent resin (for example, a fluorine-based resin), and a pore-forming agent (CaCO ₃ ) in addition to the catalyst material to form a catalyst electrode. This catalyst electrode is a porous gas diffusive catalyst electrode comprising, for example, a catalyst layer 1 made of a catalyst in which platinum (Pt) is supported on carbon and, for example, a carbon sheet 2 as a porous gas diffusible current collector. However, in a narrow sense, only the catalyst layer 1 may be referred to as a gas diffusive catalyst electrode.

  A negative electrode (fuel electrode or hydrogen electrode) 5 composed of a catalyst electrode with a terminal 4 and a positive electrode (oxygen electrode) 7 composed of a catalyst electrode with a terminal 6 are arranged to face each other, and Nafion ( A proton conducting portion 3 made of (registered trademark) (perfluorosulfonic acid resin manufactured by DuPont) or the like is sandwiched.

During the operation of the fuel cell, hydrogen gas is passed through the H ₂ flow path 8 on the negative electrode 5 side, and hydrogen ions are generated by the action of the catalyst of the catalyst layer 1 while passing through the flow path 8. The hydrogen ions move to the positive electrode 7 side through the proton conducting portion 3, where oxygen (or air) passing through the O ₂ flow path 9 reacts with oxygen ions generated by the action of the catalyst of the catalyst layer 1, thereby A desired electromotive force is taken out.

In such a fuel cell, a carbon material is widely used as a support for a noble metal such as Pt that forms a catalyst electrode. In addition, an example in which a small amount of titanium oxide such as TiO ₂ is added to a carbon material carrier has been reported (see Non-Patent Document 1 described later).

Here, the reaction at the oxygen electrode will be described in detail. As shown in FIG. 11, the dissociation product generated by adsorbing oxygen molecules (O ₂ ) to the catalytic metal (Pt) particles adhering to the carbon support and decomposing them is the fuel. It reacts with protons (H ⁺ ) that have moved from the pole side to produce water.

In this case, in order to improve the output of the fuel cell (FC), it is important to reduce the reaction resistance. However, as shown in FIG. 12, the largest resistance during power generation is the oxygen resistance on the oxygen electrode side. It is a dissociation reaction. That is, the voltage required for the oxygen dissociation reaction (reduction reaction) is an ideal change curve (O ₂ -ideal) represented by a broken line, but this is actually a change curve (O ₂ -real) represented by a solid line. The difference from the change curve of the voltage required for the hydrogen decomposition reaction on the fuel electrode side (H ₂ -real: not much different from H ₂ -ideal) is expressed as the effective voltage E _H2-PEFC (PEFC: Polymer electrolyte (solid electrolyte) ) Type fuel cell), the effective voltage is lowered due to a voltage drop due to O ₂ -real. Under ideal operating conditions, 70% or more of the total output voltage loss is caused by the slow oxygen reduction reaction on the oxygen electrode side. In the case of the direct methanol (DM) system using methanol as the fuel, the effective voltage E _DMFC further decreases because the required voltage (CH ₃ OH-real) on the fuel electrode side increases.

  As shown in FIG. 13, such a decrease in effective voltage is mainly caused by the reaction resistance on the oxygen electrode side in the region where the catalytic activity is dominant (catalytic activity dominant region). The effective voltage further decreases due to the resistance overvoltage in the region where the membrane resistance is dominant (membrane resistance dominant region) and the concentration polarization in the region where the substance is dominant (mass transfer dominant region).

Electrochimica Acta 49 (2004) 4163-4170 “Synthesis characterization of methanol tolerant Pt / TiOx / C nanocomposites for oxygen reduction in direct methanol fuel cells”

  From the above, it is desired to improve the output characteristics of the fuel cell by suppressing the reaction resistance particularly on the oxygen electrode side and increasing the catalyst efficiency.

  However, the carbon material used as the support for the metal catalyst in the catalyst electrode described above often occupies about half of the catalyst weight, but this support material has no catalytic function. In other words, half of the catalyst used for the electrode of the fuel cell is occupied by a carbon material as a carrier material that has a high surface area and only exhibits electron conduction. In recent years, studies including improvements on such carbon materials have been started. However, the studies have included changes in the shape of the carbon materials, an increase in surface area, and the like, and have not left the category of carbon materials.

  In addition, from the viewpoint of increasing the durability of fuel cells, problems have been raised regarding the use of carbon materials. The problem is that a small amount of hydrogen peroxide (see FIG. 10) generated at the oxygen electrode during power generation oxidizes the carbon material as a carrier and the carbon material is eluted. At present, there is no countermeasure for this problem, and there is a possibility that it may become a big problem when considering the long-term stability of the fuel cell.

That is, the carbon material as a catalyst carrier widely used until now has the following problems.
(1) The carbon material itself has no catalytic function, and no cocatalyst function that increases catalytic ability has been confirmed.
(2) Considering the long-term stability of the fuel cell, there is a concern about the elution of the carbon material.

Such a problem also occurs in the carbon material added with a small amount of titanium oxide shown in Non-Patent Document 1 described above. That is, this support material, for example, TiO ₂ / C, has a Pt: Ti atom number ratio of 1: 1 in a state where Pt as a catalyst metal is supported on carbon at a ratio of 20% by mass. The ratio of Ti to carbon is only about 5.6% by mass. In other words, the addition amount of Ti is only a small amount, and most of the support is made of carbon. Therefore, when viewed as a support material, there is substantially no catalytic function as described above, and durability due to elution of carbon. The performance of the fuel cell is likely to deteriorate, and in reality, the high output and stability of the fuel cell cannot be realized.

Further, as shown in FIG. 10, since the Pt particles adhering to the carbon support are small in size and scattered, the dissociation → reaction → water generation after the O ₂ molecules are adsorbed on the Pt particles. When the flow up to desorption proceeds via each Pt particle, the flow is not smooth, the reaction is slow, and the catalyst efficiency is poor.

  An object of the present invention is to overcome the problems of the conventional catalyst carrier, promote catalyst efficiency, eliminate elution of the carrier itself, and realize high durability, and a catalyst electrode comprising this catalyst electrode material And a manufacturing method thereof, a support material for forming a catalyst electrode material, and an electrochemical device using the catalyst electrode.

  That is, the present invention is formed by a support material for an electrode catalyst mainly composed of an oxide such as titanium dioxide, a catalyst electrode material in which a catalyst material such as platinum is supported on the support material, and the catalyst electrode material. This relates to the catalyst electrode.

  The present invention is also constituted by a plurality of electrodes and an ionic conductor sandwiched between these electrodes, and at least one of the plurality of electrodes, particularly the oxygen electrode, is an electric electrode comprising the catalyst electrode material of the present invention. It relates to chemical devices, in particular fuel cells.

  The present invention also includes a step of producing a support material for an electrode catalyst mainly composed of an oxide such as titanium dioxide, a step of adding a precursor of an electrode catalyst such as chloroplatinic acid to a dispersion of the support material, and an alcohol. The catalyst material in the precursor is attached to the support material by a reduction treatment such as by a catalyst, and further, by the catalyst electrode material formed by attaching the catalyst material to the support material The present invention also provides a method for producing a catalyst electrode, to which a process for forming a catalyst electrode is added.

According to the present invention, since the support material constituting the catalyst electrode is mainly made of an oxide, the material is completely different from that of the conventional carbon material support and has the following excellent effects. Can do.
(A) Utilizing the cocatalyst function exhibited by oxides to improve the catalyst efficiency and thereby improve the performance such as output characteristics, etc., especially in the low current and high voltage range. can do.
(B) In addition, the amount of noble metal catalyst used can be reduced and the cost can be reduced by improving the catalyst efficiency due to the oxide cocatalyst function.
(C) In addition, since no carbon material is used, elution due to oxidation does not occur, and long-term stability can be realized by enhancing the durability of the device.
(D) Furthermore, since it is not necessary to use an expensive functional carbon material, the cost can be reduced also in this respect.

In the present invention, it is desirable that the carrier material is composed of only the oxide in order to achieve the above-described effects. However, the carrier material is composed of only the oxide and can operate sufficiently even when no carbon material is added, but there is no problem even if a small amount of carbon material is added as a conduction aid. In addition, if the oxide has a magnetic phase of, for example, Ti _n O _2n-1 (n = 4 to 9) among titanium oxides, it has conductivity depending on the temperature. In some cases, the conductive carrier material can be composed of only oxides.

  Further, it is desirable that the oxide has a high surface area, sufficient acid resistance, and a cocatalyst function such as adsorption ability in a dissociation reaction of oxygen or the like as compared with a normal oxide.

Such oxides include titanium oxides such as TiO ₂ , vanadium oxides such as V ₂ O ₅ or VO _x , tantalum oxides such as Ta ₂ O ₅ , tungsten oxides such as H ₂ WO ₄ or WO ₃ , Antimony oxide such as SbO ₂ , molybdenum oxide such as MoO ₂ , tin oxide such as SnO ₂ , erbium oxide such as Er ₂ O ₃ , cerium oxide such as CeO ₂ , zirconium oxide such as ZrO ₂ , At least one selected from the group consisting of silicon oxides such as SiO ₂ , zinc oxides such as ZnO, magnesium oxides such as MgO, niobium oxides such as Nb ₂ O ₅ and aluminum oxides such as Al ₂ O _3. Species can be used.

Among these, nanoscale titanium dioxide is preferable, and nanowires with a diameter of nm scale or TiO ₂ that has been converted into a nanotube can be used.

  The catalyst material may be made of a noble metal, such as platinum, and may be a platinum alloy (Pt—Ti, Pt—Cr, Pt—Co, Pt—Ni, etc.).

  The support material, catalyst electrode material or catalyst electrode of the present invention is suitable for constituting at least one of the electrodes of the electrochemical device, particularly an oxygen electrode in a fuel cell.

  In the production method of the present invention, the carrier material described in any one of claims 11 to 14 is used as the carrier material, and the electrode catalyst material described in claim 15 or 16 is used as the carrier material. It is good to attach.

  In this case, when nanoscale titanium dioxide is used as the support material and platinum is used as the electrode catalyst, adding chloroplatinic acid as a precursor to the titanium dioxide dispersion can stabilize the output. It is desirable to obtain it.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

Role of Oxide Support and Catalytic Metal FIG. 1 uses titanium oxide, for example, TiO ₂ or Ti _n O _2n-1 (n = 4-9) nanowires as the oxide support according to the present invention, A catalyst electrode material in which, for example, Pt particles as a catalyst metal are attached to this oxide carrier is shown.

  This oxide carrier has a surface area higher than that of a normal oxide, has acid resistance, and also has a cocatalyst function during an oxygen dissociation reaction, and thus constitutes an oxygen electrode of a fuel cell. In this case, there is an effect of sufficiently adsorbing oxygen molecules on the surface of the carrier. When the adsorbed oxygen molecules come into contact with Pt particles having a relatively large particle size, for example, 140 nm, unlike the Pt particles on the carbon support shown in FIG. 11, a dissociation reaction occurs on the surface of the Pt particles. Further, it is considered that water reacts with protons from the fuel electrode side on the same surface to generate and desorb water. In this case, the supply of electrons is performed through the Pt particles by the contact between the Pt particles having good electrical conductivity.

  In this way, oxygen molecules are adsorbed on the surface of the support by the cocatalyst function of the oxide support, and this oxygen molecule sequentially causes a dissociation reaction and a water generation reaction on the surface of the Pt particles having a large particle size. High output can be achieved by improvement.

FIG. 2 shows the power generation effect when the oxide support is used . FIG. 2 shows the power generation characteristics obtained by using the catalyst electrode formed of the catalyst material in which Pt or an alloy thereof is adhered to the support for the fuel cell shown in FIG. Show. The preparation conditions and measurement conditions of each part of the fuel cell in this case are shown in FIG. 2 (where TKK: Tanaka Kikinzoku, CCM: Catalyst-Coated Membrane method, Ti—NW or TiO ₂ —NW: titanium oxide) Nanowire, H ₂ PtCl ₆ .6H ₂ O: Pt precursor described later).

From this result, when using the catalyst (Pt / TiO ₂ -NW) using titanium oxide as a carrier based on the present invention, it is particularly 0 to 350 mA / cm ² as compared with the case of using a carbon carrier (Pt / C). It can be seen that the effective voltage is improved in the low current region. That is, a high voltage can be obtained in a low current region, and a low current and high voltage drive is possible, and a fuel cell suitable for driving in that region is obtained.

  The reason why driving in such a low current / high voltage region is important will be described with reference to FIG.

In FIG. 3, when the power generation characteristics when Pt / C is used are □ and the output characteristics are ■, the investigation of increasing the output of the fuel cell has been widely conducted in the direction of increasing the limit current. . If the power generation characteristic in which the limit current has actually increased is Δ and the output characteristic is ▲, it can be clearly confirmed that the maximum output is increased (about 117 mW / cm ² → about 175 mW / cm ² ). However, surprisingly, when the effective voltage value at the time of generating the maximum output is compared, surprisingly, it hardly changes as follows.
116.8 mW / cm ² = 0.345 V × 338.5 mA / cm ²
175.2 mW / cm ² = 0.345 V × 507.7 mA / cm ²

  Here, “low drive voltage”, which is one of the problems of fuel cells, can be mentioned. It has been pointed out that the drive voltage for fuel cells is low compared to general batteries, and even if the maximum output rises, if it does not increase the effective voltage used at that time, most of the resistance becomes resistance. It can be considered at the same time. In actual use, driving at the maximum output is impossible from the viewpoint of resistance (loss), and use on the high voltage / low current side with less loss is expected. At the time of commercialization of the fuel cell, boosting by a DC-DC converter is conceivable, but the basic fuel cell voltage is high at this time as well, leading to a reduction in conversion loss during boosting.

Therefore, the present inventor believes that the fuel cell development policy is not limited only to the increase of the limit current, but the region that can be used at a high voltage, that is, the driving in the high voltage / low current region is a big guideline for fuel cell development. This has been realized by the use of a carrier according to the invention. In this case, an example when the limit current is not different from the above example is shown. If the power generation characteristics are ○ and the output characteristics are ●,
229.1 mW / cm ² = 0.550 V × 416.5 mA / cm ²
Compared with the above example, it can be seen that the maximum output and voltage increase without increasing the limit current. This means that when the oxide support according to the present invention is used, high voltage driving is possible in a low current region, and extremely useful performance can be obtained.

Supported synthesis and catalytic metal oxide support will now be described a supported method of preparing a titanium oxide support process and catalyst metal (Pt).

  First, titanium oxide powder (P-25) manufactured by Degasser is treated with a high-concentration alkaline solution (KOH aqueous solution) in an autoclave under the conditions shown in FIG. 4, and the resulting titanium oxide slurry is filtered, washed, and heated. Dry or freeze-dry (FD). Then, if necessary, heat treatment is performed at 300 to 800 ° C. for 60 to 160 minutes for crystallization to obtain nanowire-like titanium dioxide having a high surface area close to a compound having a layered structure. In addition, when baking after drying, crystallization progresses too much and a specific surface area (BET value) falls.

The titanium dioxide nanowire dispersion liquid freeze-dried and increased in surface area in this manner was added to a platinum precursor such as H ₂ PtCl ₆ .6H ₂ O (chloroplatinic acid) or Pt (NH ₃ ) ₂ (NO ₂ ) _2. In addition, an alcohol such as ethanol was added for reduction treatment to deposit (carry) Pt particles on the surface of titanium dioxide.

The results shown in FIG. 5 show that, according to the present invention, when Pt is deposited on a titanium dioxide support using P-25 as a starting material with H ₂ PtCl ₆ .6H ₂ O as a precursor, there is variation, but there is variation. While the characteristics are obtained, the performance is hardly obtained when the precursor is Pt (NH ₃ ) ₂ (NO ₂ ) ₂ .

The catalytic properties and activity Figure 6, conventional Pt / C catalyst, the Pt / TiO ₂ -NW catalyst according to the present invention, showing the observation result using a transmission electron microscope (TEM).

According to this, in the catalyst based on the present invention, when the precursor is H ₂ PtCl ₆ .6H ₂ O, the average particle diameter of Pt is 140.6 nm, and the precursor is Pt (NH ₃ ) ₂ (NO ₂ ). much greater than when the _2, also it can be seen that much larger than the average particle diameter of Pt conventional catalyst.

  Thus, when the catalyst activity due to such Pt particle size is compared, it can be seen that the activity is not influenced by the Pt particle size, as shown in FIG.

The catalytic metal (Pt) and Ti phase diagram 8 in the catalyst shows a 2p spectra of 4f spectra and Ti of Pt in the catalyst, the H ₂ PtCl ₆ · 6H ₂ O in the precursor in accordance with the present invention When it is used and supported on TiO ₂ -NW, the spectrum of Pt4f is shifted to the 4f _7/2 side more than when other precursors are used, and it can be seen that the metallicity of Pt is increased. . This seems to be related to the improvement in activity (improves power generation characteristics) depending on the type of precursor. For Ti, there is no difference in the spectrum.

Acid resistance of carrier in catalyst Conventionally, carbon carriers that have been widely used as catalyst carriers are concerned about elution due to oxidation. Therefore, with reference to FIG. 9, the acid resistance of TiO ₂ used as a support in this example in place of the conventionally used carbon support will be described with reference to a pH-potential diagram.

Electrocatalyst materials used in fuel cells are cathodic potential (about 1 V for standard hydrogen electrode) and anode potential (about standard hydrogen electrode) under super strong acid (pH = 0) due to proton conductor and high temperature conditions. It is essential that it is stable without eluting at about 0V). In this respect, carbon widely used as a catalyst carrier is a thermodynamically unstable material, and there is a concern about its stability particularly at a high potential. On the other hand, from FIG. 9, it is expected that Ti thermodynamically exists stably in the form of TiO ₂ and does not elute even under various conditions in the fuel cell.

Production of Electrochemical Device As described above, after producing a catalyst material made of Pt-supported titanium oxide based on the present invention, film formation or press molding is performed on the current collector by coating, as in the structure shown in FIG. The fuel cell is produced by sandwiching the sheet-shaped catalyst material.

In addition to forming a catalyst electrode alone, this catalyst material may be mixed with an ion conductor, a water-repellent resin (for example, fluorine-based) and a pore-forming agent (CaCO ₃ ) in some cases to form a catalyst electrode. Good. This catalyst electrode is a porous gas diffusive catalyst electrode comprising, for example, a catalyst layer 1 made of a catalyst in which platinum (Pt) is supported on titanium dioxide and, for example, a carbon sheet 2 as a porous gas diffusible current collector. Is an oxygen electrode, but only this catalyst layer 1 may be a gas diffusive catalyst electrode. The fuel electrode may be formed of a normal Pt-supported carbon material.

  A negative electrode (fuel electrode or hydrogen electrode) 5 composed of a catalyst electrode with a terminal 4 and a positive electrode (oxygen electrode) 7 composed of a catalyst electrode with a terminal 6 are arranged to face each other, and Nafion ( A proton conducting portion 3 made of (registered trademark) (perfluorosulfonic acid resin manufactured by DuPont) or the like is sandwiched. The operation of this fuel cell is as described above.

  The embodiment described above can be variously modified based on the technical idea of the present invention.

  For example, when the electrochemical device according to the present invention is configured as a fuel cell, the catalyst electrode according to the present invention is preferably used at least for the oxygen electrode, but it is also used for the fuel electrode side. It's okay.

  In addition, although the proton conduction type fuel cell has been described as the electrochemical device of the present invention, a device that conducts ions other than protons may be used. Further, it can be applied to a hydrogen production apparatus using the reverse reaction of the fuel cell. Moreover, application to a metal-oxygen battery, an electrolytic cell, etc. is also possible.

  The catalyst electrode material and catalyst electrode of the present invention effectively improve the output characteristics and durability of electrochemical devices such as fuel cells, and contribute to cost reduction.

It is a general | schematic principle figure which shows the role of the oxide support | carrier and catalyst metal by embodiment of this invention. 3 is a graph showing the power generation results when using an oxide carrier. It is a graph which shows the electric power generation characteristic explaining the reason why the low current / high voltage region is important. 3 is a table showing processing conditions for increasing the surface area of the oxide support (TiO ₂ ). FIG. 6 is a graph showing the results of studies on the synthesis conditions for oxide carriers. It is a transmission electron micrograph of various catalyst materials. It is the schematic which shows the examination result about the relationship between a catalyst physical property and activity similarly. It is a spectrum figure which shows the state of the catalyst metal (Pt) and Ti in a catalyst similarly. 3 is a graph showing the acid resistance of the TiO ₂ catalyst carrier. It is a schematic sectional drawing of the electrochemical device (fuel cell) based on a prior art example (or this invention). It is a general | schematic principle figure which shows the role of the catalyst metal (Pt) carry | supported by the conventional carbon support | carrier. It is a graph which shows the electric power generation characteristic of a general fuel cell. It is a graph which shows the relationship between a current-voltage characteristic and the predominance area | region of each component similarly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Catalyst layer, 2 ... Gas permeable collector, 3 ... Ion (proton) conduction part, 4, 6 ... Terminal, 5 ... Negative electrode (fuel electrode), 7 ... Positive electrode (oxygen electrode), 8 ... Hydrogen gas flow Road, 9 ... oxygen (air) flow path

Claims (30)

  A catalyst electrode material in which a catalyst material is supported on a support material mainly composed of an oxide.   The catalyst electrode material according to claim 1, wherein the support material is composed of only the oxide.   The catalyst electrode material according to claim 1, wherein the oxide has a high surface area, acid resistance, and a promoter function.   The oxide is titanium oxide, vanadium oxide, tantalum oxide, tungsten oxide, antimony oxide, molybdenum oxide, tin oxide, erbium oxide, cerium oxide, zirconium oxide, silicon oxide, zinc The catalyst electrode material according to claim 3, comprising at least one selected from the group consisting of oxides, magnesium oxides, niobium oxides, and aluminum oxides.   The catalyst electrode material according to claim 4, wherein the titanium oxide is nanoscale titanium dioxide.   The catalyst electrode material according to claim 1, wherein the catalyst material is made of a noble metal.   The catalyst electrode material according to claim 1, wherein the catalyst material is made of platinum or a platinum alloy.   2. The catalyst electrode material according to claim 1, which is used to constitute at least one of the plurality of electrodes in an electrochemical device including a plurality of electrodes and an ionic conductor sandwiched between the electrodes. .   The catalyst electrode material according to claim 8, which is used to constitute an oxygen electrode in a fuel cell as the electrochemical device.   A support material for an electrocatalyst mainly composed of an oxide.   The support material according to claim 10, comprising only the oxide.   The support material according to claim 10, wherein the oxide has a high surface area, acid resistance and a promoter function.   The oxide is titanium oxide, vanadium oxide, tantalum oxide, tungsten oxide, antimony oxide, molybdenum oxide, tin oxide, erbium oxide, cerium oxide, zirconium oxide, silicon oxide, zinc The carrier material according to claim 12, comprising at least one selected from the group consisting of oxides, magnesium oxides, niobium oxides and aluminum oxides.   The carrier material according to claim 13, wherein the titanium oxide is nanoscale titanium dioxide.   The support material according to claim 10, wherein the electrode catalyst material is made of a noble metal.   The support material according to claim 10, wherein the electrode catalyst material is made of platinum or a platinum alloy.   The electrochemical device comprising a plurality of catalyst electrodes and an ionic conductor sandwiched between the catalyst electrodes is used for constituting at least one of the plurality of catalyst electrodes. Carrier material.   The support material according to claim 17, which is used for constituting a catalyst electrode of an oxygen electrode in a fuel cell as the electrochemical device.   The catalyst electrode formed with the catalyst electrode material of any one of Claims 1-7.   20. The catalyst electrode according to claim 19, which is used to constitute at least one of the plurality of electrodes in an electrochemical device comprising a plurality of electrodes and an ionic conductor sandwiched between the electrodes.   The catalyst electrode according to claim 20, which is used to constitute an oxygen electrode in a fuel cell as the electrochemical device.   It is comprised by the some electrode and the ionic conductor pinched | interposed between these electrodes, and at least one of the said several electrode consists of the catalyst electrode material of any one of Claims 1-7. Chemical device.   The electrochemical device according to claim 22, wherein the oxygen electrode is configured as a fuel cell made of the catalyst electrode material.   A step of producing a support material for an electrode catalyst mainly composed of an oxide, a step of adding a precursor of an electrode catalyst to a dispersion of the support material, and a catalyst material in the precursor to the support material by reduction treatment A method for producing a catalyst electrode material.   The support material according to any one of claims 11 to 14 is used as the support material, and the electrode catalyst material according to claim 15 or 16 is attached to the support material. A method for producing a catalyst electrode material.   26. The catalyst electrode material according to claim 25, wherein, when nanoscale titanium dioxide is used as the support material and platinum is used as the electrode catalyst, chloroplatinic acid is added as the precursor to the titanium dioxide dispersion. Manufacturing method. In an electrochemical device comprising a plurality of electrodes and an ionic conductor sandwiched between these electrodes, a method for producing a catalyst electrode used to constitute at least one of the plurality of electrodes,
A structure for producing a support material for an electrocatalyst mainly composed of an oxide;
Adding an electrocatalyst precursor to the carrier material dispersion;
Attaching the catalyst material in the precursor to the support material by reduction treatment;
Forming a catalyst electrode with a catalyst electrode material formed by adhering the catalyst material to the carrier material.   The support material according to any one of claims 11 to 14 is used as the support material, and the electrode catalyst according to claim 15 or 16 is attached to the support material. A method for producing a catalyst electrode.   28. The catalyst electrode according to claim 27, wherein, when nanoscale titanium dioxide is used as the support material and platinum is used as the electrode catalyst, chloroplatinic acid is added as a precursor to the titanium dioxide dispersion. Production method. 28. The method for producing a catalyst electrode according to claim 27, wherein a catalyst electrode used for constituting an oxygen electrode is produced in the fuel cell as the electrochemical device.

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