JP2008100227A - Conductive catalyst particle and its manufacturing method, gas-diffusing catalyst electrode, and electrochemical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide conductive catalytic particles exhibiting outstanding catalytic properties without causing sintering and a process for production thereof, a gas-diffusing catalytic electrode, and an electrochemical device. <P>SOLUTION: Conductive catalytic particles are composed of a conductive powder and a catalytic material adhering to the surface thereof. The catalytic material is an alloy of MI and MII (where MI denotes at least one species selected from noble metal elements such as Pt, Ir, Pd, Rh, Au and Ru; MII denotes at least one species selected from Co, Ni, Cr, Al, Cu, Hf, Zr, Ti, V, Nb, Ta, W, Ga, Ge, Si, Re, Os, Pb, Bi, Sb, Mo, O, N, F, C, Zn, In and rare earth elements). The conductive catalytic particles are produced by causing MI and MII to adhere at the same time to the surface of the conductive powder by physical vapor deposition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to conductive catalyst particles and a method for producing the same, a gas diffusing catalyst electrode, and an electrochemical device.

  Conventionally, a gas diffusive catalyst electrode is formed by forming catalyst particles in which platinum as a catalyst material is supported on carbon as conductive powder together with, for example, a fluororesin and an ion conductor as water-repellent resins ( Japanese Patent Laid-Open No. 5-36418) or a process of coating on a carbon sheet.

When this electrode is used as an electrode for hydrogen decomposition constituting a fuel cell such as a polymer electrolyte fuel cell, the fuel is ionized by a catalyst material such as platinum, and the generated electrons flow through the conductive carbon. Protons (H ⁺ ) generated by ionizing hydrogen flow to the ion conductive membrane via the ion conductor. Here, a catalyst material such as a gap for passing gas, carbon for passing electricity, an ion conductor for passing ions, and platinum for ionizing fuel and an oxidant is required.

  Usually, as a method of attaching platinum (catalyst material) to the surface of carbon powder as conductive powder, first, platinum is ionized into a liquid state, and carbon powder is immersed in a solution containing platinum. There is a method in which platinum is attached to the body, followed by reduction and heat treatment to make it adhere as fine platinum on the surface of the carbon powder (Japanese Patent No. 2879649).

  However, the conventional method as described above requires reduction and heat treatment to support platinum on the carbon powder. For example, when the temperature in this heat treatment is low, the crystallinity of platinum deteriorates, There is a problem that good catalytic properties cannot be obtained.

Further, the fuel is ionized by the catalyst material such as platinum as described above, and the generated electrons flow through the conductive carbon, and protons (H ⁺ ) generated by ionizing hydrogen are ionized via the ion conductor. Flows through conductive film. Accordingly, since the carbon powder and the ionic conductor need to be in contact with each other, the ionic conductor is usually applied after platinum is supported on the carbon powder. However, since platinum functions only in the portion in contact with the gas, the platinum having no contact portion with the gas by the ion conductor does not function.

  As an alternative, there is a method of supporting platinum after applying an ion conductor to carbon powder. However, heat treatment must be performed to improve the crystallinity of platinum. However, since ion conductors generally have low heat resistance, when heated to a heat treatment temperature that improves the crystallinity of platinum, the ion conductor Will deteriorate.

  FIG. 16A is a schematic cross-sectional view showing conductive catalyst particles obtained by supporting platinum 27 on carbon powder 1 by a conventional manufacturing method, and FIG. It is a schematic sectional drawing which shows the electroconductive catalyst particle obtained by making platinum 27 carry | support on it, after making the ion conductor 11 adhere.

  As is clear from FIG. 16A, in the conductive catalyst particles supporting platinum obtained from the liquid phase, platinum 27 exists in a spherical shape on the surface of the carbon powder 1, so that the platinum 27 is carbon powder 1. It is easy to move away from the surface of the metal and requires a large amount of platinum in the production process. Furthermore, since the platinum 27 exists in a spherical shape, only the surface of the platinum 27 functions as a catalyst material, the interior does not function, and the efficiency of the catalytic activity is low with respect to the amount of platinum. Although not shown, platinum 27 also enters the pores existing on the surface of the carbon powder 1. For this reason, there is platinum 27 that does not function effectively, and the catalytic efficiency is low with respect to the amount of platinum.

  As shown in FIG. 16B, when the platinum 27 is supported after the ion conductor 11 is applied to the carbon powder, heat treatment for improving the crystallinity of the platinum 27 is necessary as described above. However, the ion conductor 11 generally has low heat resistance, and when heated to a heat treatment temperature that makes the crystallinity of the platinum 27 good, the ion conductor 11 deteriorates.

  As a result of intensive studies to solve the above-described problems, the present inventor proposed a gas diffusive catalytic electrode having a good catalytic action with a smaller amount of catalyst in Japanese Patent Application Laid-Open No. 2002-110175 (described later). Patent Document 1).

  That is, according to the invention according to Japanese Patent Laid-Open No. 2002-110175 (hereinafter referred to as the invention of the prior application), the carbon powder disposed in the container 6 using a physical vapor deposition method such as a sputtering method as shown in FIG. By attaching platinum (catalyst material) to the surface of the body (conductive powder) 1, it is possible to obtain conductive catalyst particles having platinum 27 attached to the surface of the carbon powder 1 as shown in FIG. it can.

  That is, as shown in FIG. 18A, platinum 27 is attached only to the surface of the carbon powder 1 in the conductive catalyst particles obtained by using the physical vapor deposition method. Therefore, good catalytic action can be obtained with a smaller amount, and a sufficient contact area between the platinum 27 and the gas is ensured, so that the specific surface area of the platinum 27 contributing to the reaction is increased and the catalytic performance is also improved. To do.

  Further, as shown in FIG. 18B, an ion conductor 11 is attached to the surface of the carbon powder 1, and further, platinum 27 is attached to the surface of the ion conductor 11 by physical vapor deposition. Thus, it is not necessary to perform a heat treatment for improving the crystallinity of platinum, and the platinum 27 can be adhered without impairing the performance of the ion conductor 11.

JP 2002-110175 (Claims, paragraphs [0021] to [0030] on page 4, [FIG. 1], [FIG. 2] in the drawings)

  However, the present inventor has found that the invention of the prior application has points to be improved while having the above-described excellent features.

  When the catalyst material is deposited on the surface of the conductive powder by a physical vapor deposition method such as sputtering, for example, when using a highly pure catalyst material as a target, it is compared with the conventional chemical deposition method as described above. Thus, a very pure catalyst material can be deposited. However, when the purity of the catalyst material adhering to the surface of the conductive powder is high, the initial catalytic activity is high during use as a fuel cell, but sintering tends to occur between the catalyst particles due to the temperature rise with time. However, there is a problem that the activity is reduced by this sintering. Further, when a gas diffusive catalyst electrode containing conductive catalyst particles having a high purity of the catalyst material is used in, for example, a fuel cell, there is a problem that the output is reduced by this sintering.

  In addition, the catalytic activity of the catalyst material increases as the crystal grain size decreases. The initial particle size of the catalyst material in the physical vapor deposition method is determined when the catalyst material adheres to the conductive powder. However, when the purity of the catalyst material is high, the crystal particle size tends to increase. For this reason, in order to obtain high catalyst activity with high purity of the catalyst material, it was necessary to study the refinement of the crystal grain size of the catalyst material.

  The present invention has been made in order to improve the insufficient points while taking advantage of the above-mentioned features of the invention of the prior application, and the object thereof is to provide a conductive material that does not cause sintering and has excellent catalytic characteristics. It is an object to provide a conductive catalyst particle and a manufacturing method thereof, a gas diffusing catalyst electrode and a manufacturing method thereof, and an electrochemical device.

  As a result of intensive studies to solve the above-described problems, the present inventor needs to prevent internal self-diffusion of the crystal lattice of the catalyst material in order to prevent sintering of the catalyst material. In order to prevent self-diffusion, if a specific element is forcibly introduced into the crystal lattice of the noble metal material and this is used as a catalyst material, an anti-sintering effect can be obtained, resulting in better catalytic activity. The present invention has been found.

  That is, in the present invention, on the surface of the conductive powder, MI (where MI is at least one selected from noble metal elements consisting of Pt, Ir, Pd, Rh, Au, or Ru) and MII ( However, MII is Co, Ni, Cr, Al, Cu, Hf, Zr, Ti, V, Nb, Ta, W, Ga, Ge, Si, Re, Os, Pb, Bi, Sb, Mo, O, N, F, C, Zn, In, and at least one selected from rare earth elements), and a catalyst material made of an alloy with the conductive catalyst particles attached thereto, Conductive catalyst particles obtained by simultaneously attaching the MII to the surface of the conductive powder by a physical vapor deposition method, whereby a catalyst material made of an alloy of the MI and the MII is attached. This relates to the manufacturing method.

  Further, the present invention relates to a gas diffusing catalyst electrode containing conductive catalyst particles in which a catalyst material made of an alloy of MI and MII is attached to the surface of a conductive powder.

  Further, the present invention comprises at least two electrodes and an ionic conductor sandwiched between these electrodes, and the gas diffusive catalyst electrode of the present invention described above constitutes at least one of the electrodes. The present invention relates to an electrochemical device.

  According to the present invention, the MII and the MII are simultaneously adhered to the surface of the conductive powder by the physical vapor deposition method, so that the MII can be forcibly introduced into the crystal lattice of the MI. Thus, conductive catalyst particles can be obtained in which the catalyst material made of an alloy of MI and MII adheres to the surface of the conductive powder. Since the conductive catalyst particles contain the MII in the catalyst material, the movement of the transition of the MI in the catalyst material is inhibited, and the internal self-diffusion of the crystal lattice is prevented, as described above. Generation of sintering can be prevented.

  Further, since the catalyst material is attached to the surface of the conductive powder by the physical vapor deposition method, the catalyst material having good crystallinity can be attached to the surface of the conductive powder at a low temperature, The obtained conductive catalyst particles of the present invention can obtain a good catalytic action with a smaller amount of the catalyst material, and a sufficient contact area between the catalyst material and gas contributes to the reaction. The specific surface area of the catalyst material is increased and the catalytic performance is also improved.

  Moreover, according to the electrochemical device of the present invention, since the gas diffusive catalyst electrode of the present invention constitutes at least one of the electrodes, the occurrence of sintering can be prevented, Good output characteristics can be obtained, and the output characteristics can be maintained for a long time.

  Hereinafter, the present invention will be described more specifically based on embodiments.

  In the manufacturing method based on this invention, it is desirable to apply the sputtering method using the target which consists of said MI and said MII as said physical vapor deposition method. The sputtering method can be easily produced, has high productivity, and has good film formability.

  In addition to the sputtering method, a pulse laser deposition method may be applied as the physical vapor deposition method. The pulse laser deposition method is easy to control in film formation and has good film formability.

  In the above-described chemical deposition method according to the prior art, usually, the MII is introduced into the MI by diffusion by heating. During such heating, the particle size increases due to sintering. End up. On the other hand, in the manufacturing method according to the present invention, the MII and the MII are simultaneously adhered to the surface of the conductive powder by the physical vapor deposition method such as the sputtering method. It can be forcibly introduced into the crystal lattice without heating. Thereby, it is possible to obtain conductive catalyst particles in which the catalyst material made of an alloy of MI and MII adheres to the surface of the conductive powder, and the present invention containing the conductive catalyst particles. In the gas diffusive catalyst electrode based on the above, since the internal self-diffusion of the crystal lattice of the MI is prevented by the MII, the sintering is more difficult to occur.

  Furthermore, since the catalyst material is deposited by the sputtering method or the pulse laser deposition method, the catalyst material having good crystallinity can be deposited on the surface of the conductive powder at a low temperature, and the resulting invention is obtained. The conductive catalyst particles based on the catalyst material can obtain a good catalytic action with a smaller amount of the catalyst material, and a sufficient contact area between the catalyst material and the gas is ensured. The specific surface area of the catalyst increases and the catalytic ability can be improved.

  Here, in Japanese Patent Application Laid-Open No. 11-510311, an example is described in which a noble metal is formed by sputtering on a carbon sheet. However, the production method according to the present invention uses the catalyst material on the surface of conductive powder. Since it is made to adhere, the specific surface area of the catalyst material contributing to the reaction can be increased and the catalytic performance can be improved as compared with the above-mentioned JP-A-11-510311.

The catalyst material is an MI-MII'-MII "alloy (where MI is at least one selected from noble metal elements consisting of Pt, Ir, Pd, Rh, Au, or Ru. MII 'is Fe, Co, It is at least one selected from Ni, Cr, Al, Sn, Cu, Mo, W, O, N, F and C. MII "is Hf, Zr, Ti, V, Nb, Ta, Ga, Ge, And at least one selected from Si, Re, Os, Pb, Bi, Sb, Mn, and rare earth elements), and the composition is MI _a -MII ′ _b -MII ″ _c In order to prevent more effectively and to have more excellent catalytic ability, it is more preferable that a + b + c = 100 at%, 0.5 at% ≦ b + c ≦ 60 at%, b ≦ 60 at%, c ≦ 20 at%.

  When the value of b + c is less than 0.5 at%, the amount of addition of MII ′ and MII ″ may be too small, so that the anti-sintering effect may be reduced, and when it exceeds 60 at%, the MII ′ and Since the amount of MII ″ added is too large, the catalytic action is likely to be reduced, and when the gas diffusible catalyst electrode containing the conductive catalyst particles according to the present invention is used for, for example, a fuel cell, the output may be reduced. is there.

  The amount of MII or MII ′ (at least one selected from Fe, Co, Ni, Cr, Al, Sn, Mo, Cu, W, O, N, F, and C) is 60 at% or less. Within this range, better catalytic action can be obtained and more effective anti-sintering effect can be obtained. In addition, the catalytic activity can be further improved. If it exceeds 60 at%, the amount of MII ′ added is too large, so that the catalytic action tends to be reduced, and the output may be reduced.

  Further, the MII or the MII ″ (at least one selected from Hf, Zr, Ti, V, Nb, Ta, Ge, Ga, Si, Re, Os, Pb, Bi, Sb, Mn and rare earth elements). The amount of addition is desirably 20 at% or less in order to obtain better catalytic action and more effective anti-sintering effect. It tends to be defective and the output may decrease.

  It is preferable that the conductive powder is vibrated when the MI and the MII are attached to the surface of the conductive powder by the physical vapor deposition method such as the sputtering method. More preferably, the body and the vibration amplifying means are arranged on the vibration surface, and while these are vibrated, the MI and the MII are adhered to the surface of the conductive powder by the physical vapor deposition method. As a result, the conductive powder is more vibrated and sufficiently mixed, and does not stay in one place on the vibration surface. Therefore, the conductive powder is exposed not only on the surface of the powder layer but also on the inside, so that the catalyst material made of the alloy of MI and MII is applied to all the conductive powder. And more uniformly.

  FIG. 1 is a schematic cross-sectional view of an example of an apparatus for producing conductive catalyst particles according to the present invention.

  As shown in FIG. 1A, when the catalyst material is attached to the surface of the conductive powder 1 by the sputtering method using the target 4 made of, for example, MI12 and MII13 as the physical vapor deposition method, A ball 5 having a smooth surface is used as a vibration amplifying means, and the conductive powder 1 and the ball 5 are mixed and placed on the vibration surface 7 in the same container 6, for example, a vibration comprising an electromagnetic coil type or an ultrasonic horn. The vibration is preferably applied by the child 8. By using the vibration device 9 configured as described above, the conductive powder 1 collides with the ball 5, mixes and flows, and does not stay at one place on the vibration surface 7. And by the said sputtering method, not only the surface of the powder layer of the electroconductive powder 1 but also the inside will come out to the surface in the container 6, and it is more uniform with respect to the entire electroconductive powder 1. The catalyst material can be adhered to the substrate.

  In this case, the ball 5 is preferably a ceramic or metal ball having a diameter of 1 to 10 mm.

  Further, as shown in FIG. 1B, the target 4 preferably has a structure in which MII 13 is introduced with respect to MI 12, and only by the physical vapor deposition method such as the sputtering method using such a target 4. It is possible to forcibly introduce MII13 into the crystal lattice of MI12 without heating.

  In the conductive catalyst particle according to the present invention, as shown in FIG. 2A, the catalyst material 14 made of an alloy of MI and MII is attached only to the surface of the conductive powder 1. In the gas diffusive catalyst electrode according to the present invention containing the conductive catalyst particles, internal self-diffusion in the crystal lattice of MI is effectively prevented by the MII, and the occurrence of sintering can be further prevented. it can.

  In addition, a good catalytic action can be obtained with a smaller amount of the catalyst material 14, and a sufficient contact area between the catalyst material 14 and the gas is ensured, so that the specific surface area of the catalyst material 14 contributing to the reaction is increased. The catalytic ability is also improved.

  In addition, as shown in FIG. 2B, the catalyst material 14 made of an alloy of MI and MII may be unevenly adhered to the surface of the conductive powder 1, and in this case, FIG. It has excellent characteristics similar to those of the conductive catalyst particles based on the present invention having the structure (A).

  Further, as shown in FIG. 2 (C), an ion conductor 11 is attached to the surface of the conductive powder 1, and the surface of the ion conductor 11 is further contacted with the MI and the MII by the physical vapor deposition method. Since the catalyst material 14 made of an alloy can be attached, it is not necessary to perform a heat treatment for improving the crystallinity of the catalyst as in the prior art, and the catalyst material 14 can be formed without impairing the performance of the ion conductor 11. Can be attached.

  The conductive catalyst particles based on any one of the present inventions (A), (B), and (C) shown in FIG. 2 have a catalytic material for the conductive powder 1 in order to exhibit both catalytic ability and conductivity. 14 is preferably deposited at a rate of 10 to 1000% by weight.

  FIG. 3 is a schematic view of a container 6 in which a conductive powder 1 and a ball 5 as the vibration amplifying means are arranged by a method for producing conductive catalyst particles according to the present invention.

  As shown in FIG. 3, the ratio of the total area A of the balls 5 to the area S of the distribution region of the conductive powder 1 is preferably 30 to 80%. If this ratio is too small, mixing of the conductive powder 1 will be insufficient, and if it is too large, the ratio of the conductive powder 1 will be small and the adhesion efficiency of the catalyst material by sputtering will be poor, and the catalyst Production efficiency of the catalyst particles to which the material is adhered becomes insufficient.

  FIG. 4 shows a partially enlarged schematic cross-sectional view of a container 6 in which the conductive powder 1 and the ball 5 as the vibration amplifying means are arranged, and the vibration with respect to the layer thickness t formed by the conductive powder 1. It is preferable that the diameter R of the ball 5 as the amplifying means is 10 to 70%. If the diameter is out of the range, it is disadvantageous for the same reason as in the case of the area ratio.

  Further, the frequency of the vibration applied to the conductive powder 1 and the ball 5 as the vibration amplification means by the vibrator 8 is 5 to 200 Hz in order to mix the conductive powder 1 sufficiently. The amplitude of the vibration is preferably ± (0.5 to 20) mm for the same reason (hereinafter, the same applies to other embodiments).

  If the catalyst material is adhered to the surface of the conductive powder under the environment within each preferable range of conditions as described above, for example, by the sputtering method, the conductive powder is further improved. Therefore, the catalyst material can be more uniformly attached to the surface of the conductive powder. When deviating from the above ranges, that is, when the ball diameter is less than 1 mm or more than 15 mm, when the frequency is less than 5 Hz or more than 200 Hz, or when the amplitude is less than ± 0.5 mm In such a case, the conductive powder cannot vibrate well, and the conductive powder stays at the bottom of the container without flowing, resulting in a non-uniform film formation. Sometimes. In addition, when the amplitude exceeds 20 mm, the conductive powder may jump out and the yield may be reduced.

  In the manufacturing method according to the present invention, instead of the ball, as the vibration amplifying means, a part that is substantially planar and has a substantially spiral, substantially concentric, or substantially folded pattern is used. The component is placed on the container so that at least a part thereof is not fixed (that is, the component itself vibrates freely in three dimensions: the same applies hereinafter), and the conductive powder is placed on the component. A body may be placed and the vibration may be applied.

  FIG. 5 is a schematic diagram of a vibration device that can be used in the manufacturing method according to the present invention, using a component 15 that is substantially planar and has a substantially spiral pattern as the vibration amplification means. It is.

  FIG. 6 shows a manufacturing based on the present invention using a component 16 that is formed in a substantially planar and substantially concentric pattern (that is, connected in a radial direction) as the vibration amplifying means. It is a schematic sectional drawing of the vibration apparatus which can be used for a method.

  FIG. 7 is a schematic cross-sectional view of a vibration device that can be used in the manufacturing method according to the present invention, using a component 17 that is substantially planar and has a substantially folded pattern as the vibration amplification means. FIG.

  In any case shown in FIG. 5 to FIG. 7, the component 15, 16 or 17 is placed in an unfixed state on at least a part of the container 6, and the conductive material is placed on the component 15, 16 or 17. When the powder 1 is placed and the vibration is applied, the shape of the component 15, 16 or 17 vibrates while being held, so that the conductive powder 1 can be further vibrated and flow better. . At this time, if the catalyst material is attached to the surface of the conductive powder 1 by the physical vapor deposition method such as the sputtering method, the conductive powder 1 in the container 6 is not only the surface but also the internal one. In addition, the catalyst material can be uniformly deposited over the entire surface.

  In obtaining such an effect, the part formed in a substantially spiral, substantially concentric or substantially folded pattern is a metal wire having a diameter of 1 to 10 mm, and has a substantially spiral, substantially concentric or substantially folded shape. The outer diameter of the part formed in the pattern is preferably 5 mm smaller than the inner diameter of the container, and the pattern pitch is preferably 5 to 15 mm. When the conditions are outside these values, mixing of the conductive powder tends to be insufficient, and the adhesion efficiency of the catalyst material tends to decrease.

  Further, for the same reason as the case of using the above-described ball, the vibration amplifying means is substantially planar and substantially spiral, substantially concentric, or substantially folded with respect to the layer thickness formed by the conductive powder. The thickness of the part formed so as to form a pattern is preferably 10 to 70%.

The electrical resistance of the conductive powder 1 is preferably 10 ⁻³ Ω · m or less, and at least of carbon, ITO (Indium tin oxide: Indium oxide doped with tin) and SnO _2. One type is preferably used.

When carbon is used as the conductive powder 1, the specific surface area of the carbon is preferably 300 m ² / g or more. When the carbon is less than 300 m ² / g, the characteristics as conductive catalyst particles may be deteriorated.

  Moreover, when the gas diffusive catalyst electrode based on this invention is produced using the conductive catalyst particle based on this invention, gas permeability becomes an important performance, but when using carbon as the conductive powder 1, When the carbon oil absorption is 200 ml / 100 g or more, good gas permeability can be obtained.

  The conductive catalyst particles according to the present invention can themselves form a catalyst layer by pressing or the like. However, when the conductive catalyst particles are formed by binding with a resin, the conductive catalyst powder is converted into a porous gas diffusible current collector. Since it can hold | maintain with sufficient intensity | strength above, it is more preferable on manufacture of the gas-diffusible catalyst electrode based on this invention.

As described above, the gas diffusible catalyst electrode according to the present invention is substantially composed of only the conductive catalyst particles according to the present invention, or the particles other than the conductive catalyst particles according to the present invention are bonded. Other components such as a resin for wearing may be contained. In the latter case, the other components include a water-repellent resin (for example, fluorine-based) in terms of binding and drainage, a pore-forming agent (for example, CaCO ₃ ) in terms of gas permeability, and transfer of protons and the like. From the viewpoint of safety, it is preferable to use an ion conductor or the like. Furthermore, the conductive catalyst particles according to the present invention are preferably held on a porous gas diffusible current collector (for example, a carbon sheet).

  The gas diffusive catalytic electrode based on this invention is applicable to the electrochemical device comprised as a fuel cell or a hydrogen production apparatus.

  For example, in a basic structure composed of a first pole, a second pole, and an ionic conductor sandwiched between the two poles, at least the first pole of the first pole and the second pole is the present invention. A gas diffusive catalytic electrode based on can be applied.

  More specifically, the gas diffusible catalyst electrode according to the present invention can be preferably applied to an electrochemical device or the like in which at least one of the first electrode and the second electrode is a gas electrode. .

FIG. 8 shows a fuel cell of a specific example using, for example, a gas diffusing catalyst electrode according to the present invention. Here, in the catalyst layer 18 in FIG. 8, the catalyst material made of an alloy of the MI (for example, Pt) and the MII (for example, Co) adheres to the surface of the conductive powder (for example, carbon powder). In addition to the conductive catalyst particles according to the present invention, in some cases, a mixed layer comprising a mixture of an ionic conductor, a water-repellent resin (for example, a fluorine-based resin) and a pore-forming agent (CaCO ₃ ). The gas diffusive catalyst electrode based thereon is a porous gas diffusible catalyst electrode comprising a catalyst layer 18 and, for example, a carbon sheet 19 as a porous gas diffusible current collector. However, in a narrow sense, only the catalyst layer 18 may be referred to as a gas diffusive catalyst electrode. Moreover, the ion conduction part 20 is pinched | interposed between the 1st pole using the gas diffusible catalyst electrode based on this invention, and a 2nd pole.

This fuel cell comprises a gas diffusible catalyst according to the present invention with a terminal (21), a negative electrode (fuel electrode or hydrogen electrode) 22 using a gas diffusible catalyst electrode according to the present invention, and a terminal (23). It has a positive electrode (oxygen electrode) 24 using an electrode (however, this is not necessarily used for the positive electrode), and the ion conducting portion 20 is sandwiched between these two electrodes. In use, hydrogen is passed through the H ₂ flow path 25 on the negative electrode 22 side. Hydrogen ions are generated while the fuel (H ₂ ) passes through the flow path 25, and the hydrogen ions move to the positive electrode 24 side together with the hydrogen ions generated at the negative electrode 22 and the hydrogen ions generated at the ion conduction unit 20. It reacts with oxygen (air) passing through the O ₂ flow path 26, and thereby a desired electromotive force is taken out.

In such a fuel cell, since the gas diffusible catalyst electrode according to the present invention constitutes the first electrode and the second electrode, sintering does not easily occur and the catalyst has a good catalytic action. Since a sufficient contact area between the material and the gas (H ₂ ) is ensured, the specific surface area of the catalyst material contributing to the reaction is increased, the catalytic ability is improved, and good output characteristics are obtained. Further, hydrogen ions are dissociated in the negative electrode 22, and hydrogen ions are dissociated in the ion conducting unit 20, and hydrogen ions supplied from the negative electrode 22 side move to the positive electrode 24 side, so that the hydrogen ion conductivity is high. There are features.

  FIG. 9 shows a hydrogen production apparatus of a specific example using, for example, a gas diffusing catalyst electrode according to the present invention on the first electrode and the second electrode.

Here, the reaction in each electrode is shown below.
Positive electrode: H ₂ O → 2H ⁺ + 1 / 2O ₂ + 2e ⁻
Negative electrode: 2H ⁺ + 2e ⁻ → H ₂ ↑
The required theoretical voltage is 1.23V or higher.

In the catalyst layer 18 ′ in FIG. 9, the catalyst material made of an alloy of MI (for example, Pt) and MII (for example, Co) is formed into a film on the surface of the conductive powder (for example, carbon powder). In addition to the attached conductive catalyst particles according to the present invention, in some cases, a mixed layer composed of a mixture of an ionic conductor, a water-repellent resin (for example, a fluorine-based resin) and a pore-forming agent (CaCO ₃ or the like), The gas diffusive catalyst electrode according to the present invention is a porous gas diffusible catalyst electrode comprising a catalyst layer 18 ′ and, for example, a carbon sheet 19 ′ as a porous gas diffusible current collector. Further, an ion conducting portion 20 ′ is sandwiched between the first electrode using the gas diffusible catalyst electrode according to the present invention and the second electrode.

  In use, this hydrogen production apparatus is supplied with water vapor or water vapor-containing air on the positive electrode 24 ′ side, and the water vapor or water vapor-containing air is decomposed on the positive electrode 24 ′ side to generate electrons and protons (hydrogen ions). The generated electrons and protons move to the negative electrode 22 ′ side, and are converted into hydrogen gas on the negative electrode 22 ′ side, whereby desired hydrogen gas is generated.

  In such a hydrogen production apparatus, since the gas diffusive catalyst electrode according to the present invention constitutes at least the first electrode of the first electrode and the second electrode, sintering hardly occurs, and the above-described negative electrode 22 ′ The protons and electrons necessary for the production of hydrogen in can move smoothly in the electrode.

  The ion conductor usable in the gas diffusing catalyst electrode according to the present invention or in the ion conducting portion sandwiched between the first electrode and the second electrode constituting the electrochemical device. In addition to general Nafion (perfluorosulfonic acid resin manufactured by DuPont), fullerene derivatives such as fullerenol (polyhydroxy fullerene) can be used.

  As shown in FIG. 10, a fullerenol having a structure in which a plurality of hydroxyl groups are added to a fullerene molecule was first reported by Chiang et al. In 1992 (Chiang, LY; Swirczewski, JW; Hsu, CS ; Chowdhury, SK; Cameron, S .; Creegan, K., J. Chem. Soc, Chem. Commun. 1992, 1791).

The present applicant makes such fullerenol an aggregate as schematically shown in FIG. 11 (A), so that an interaction occurs between the hydroxyl groups of adjacent fullerenol molecules (in the figure, ◯ indicates a fullerene molecule). As a result, it has been found for the first time that this aggregate exhibits a high proton conductivity as a macro aggregate (in other words, dissociation of H ⁺ from the phenolic hydroxyl group of the fullerenol molecule).

In addition to the fullerenol, for example, a fullerene aggregate having a plurality of OSO ₃ H groups can be used as the ion conductor. A polyhydroxylated fullerene as shown in FIG. 11B in which the OH group is replaced with an OSO ₃ H group, that is, a hydrogen sulfated fullerenol, was also reported in 1994 by Chiang et al. (Chiang. LY; Wang, LY; Swirczewski, JW; Soled, S .; Cameron, S., J. Org. Chem. 1994, 59, 3960). Some fullerenes hydrogenated with hydrogen sulfate include only an OSO ₃ H group in one molecule, or it is possible to have a plurality of these groups and hydroxyl groups.

When a large number of the above-mentioned fullerenol and hydrogen sulfate esterified fullerenol are aggregated, the proton conductivity exhibited as a bulk is that protons derived from a large amount of hydroxyl groups and OSO ₃ H groups originally contained in the molecule are directly involved in migration. There is no need to take in hydrogen or protons originating from water vapor molecules from the atmosphere, and there is no need for replenishment of moisture from the outside, in particular, absorption of moisture from the outside air, and there is no restriction on the atmosphere. Therefore, it can be used continuously even in a dry atmosphere.

In addition, fullerene, which is the base of these molecules, has particularly electrophilic properties, and this greatly contributes to the promotion of ionization of hydrogen ions not only in highly acidic OSO ₃ H groups but also in hydroxyl groups and the like. The proton conductivity is considered to be excellent. In addition, since a large number of hydroxyl groups, OSO ₃ H groups, and the like can be introduced into one fullerene molecule, the number density of protons involved in conduction per unit volume of the conductor is greatly increased. Expresses the electrical conductivity.

  Most of the above-mentioned fullerenol and hydrogen sulfate esterified fullerenol are composed of carbon atoms of fullerene, and thus are light in weight, hardly change in quality, and contain no pollutants. Fullerene production costs are also rapidly decreasing. From the viewpoint of resources, environment, and economy, fullerene is considered to be a near ideal carbon-based material more than any other material.

Further, the fullerene molecules, for example the -OH, -COOH besides -OSO ₃ H, -SO ₃ H, also those having any of -OPO (OH) ₂ can be used.

  In order to synthesize the fullerenol and the like, a desired group may be introduced into the constituent carbon atoms of the fullerene molecule by appropriately combining known treatments such as acid treatment and hydrolysis with the fullerene molecule powder. it can.

  Here, when the fullerene derivative is used as the ionic conductor constituting the ionic conduction part, the ionic conductor may be substantially made of only the fullerene derivative or bound by a binder. preferable.

  Instead of the ionic conductor sandwiched between the first electrode and the second electrode, which is composed only of the film-like fullerene derivative obtained by pressure-molding the fullerene derivative, the binder is bound by a binder. The fullerene derivative may be used for the ion conducting portions 17 and 17 ′. In this case, an ion conducting portion having sufficient strength can be formed by being bound by the binder.

  Here, as the polymer material that can be used as the binder, one or two or more kinds of polymers having a known film-forming property are used, and the compounding amount in the ion conductive part is usually 20% by weight. Keep it below. This is because if it exceeds 20% by weight, the conductivity of hydrogen ions may be reduced.

  Since the ion conducting part having such a configuration also contains the fullerene derivative as an ion conductor, it can exhibit the same hydrogen ion conductivity as the above-described ion conductor consisting essentially of the fullerene derivative.

  In addition, unlike the case of fullerene derivative alone, it has film-forming properties derived from polymer materials, and has a higher strength and more flexible ion conduction than gas fullerene derivative powder compression molded products. Can be used as a conductive thin film (thickness is usually 300 μm or less).

  The polymer material is not particularly limited as long as it does not inhibit hydrogen ion conductivity as much as possible (by reaction with the fullerene derivative) and has film-forming properties. Usually, those having no electronic conductivity and good stability are used. Specific examples thereof include polyfluoroethylene, polyvinylidene fluoride, polyvinyl alcohol and the like, and these are preferable polymer materials for the following reason.

  First, polyfluoroethylene is preferable because a thin film having a higher strength can be easily formed with a small amount of blending than other polymer materials. In this case, the blending amount is as small as 3% by weight or less, preferably 0.5 to 1.5% by weight, and the thickness of the thin film can usually be reduced from 100 μm to 1 mm.

  Moreover, the reason why polyvinylidene fluoride and polyvinyl alcohol are preferred is that an ion conductive thin film having a better gas permeation preventing ability can be obtained. In this case, the blending amount is preferably in the range of 5 to 15% by weight.

  Whether it is polyfluoroethylene, polyvinylidene fluoride or polyvinyl alcohol, if the blending amount thereof falls below the lower limit value of each of the above ranges, the film formation may be adversely affected.

  In order to obtain a thin film of an ion conducting portion in which each fullerene derivative of this embodiment is bound by a binder, a known film forming method may be used including pressure molding and extrusion molding.

  Hereinafter, the present invention will be specifically described based on examples.

Example 1
Using the apparatus shown in FIG. 1A, a sputtering target, a vibrator, and a container were placed, and conductive powder and a ball as the vibration amplification means were placed in the container. As the sputter target, as shown in FIG. 1B, a material obtained by introducing 3 at% of each additive element as MII shown in Table 1 below with respect to Pt having a particle diameter of 100 mm as MI was used. The balls used were stainless steel balls having a diameter of 3 mm, and the conductive powder was carbon powder having a surface area of 800 m ² / g and an oil absorption of 360 ml / 100 g. Then, sputtering was performed using the vibrator while generating vibration with a vibration of ± 1 mm and a vibration frequency of 36 Hz.

  Under the conditions described above, 1 g of carbon powder and 35 g of stainless steel balls are placed in the container, Ar (1 Pa) is introduced as the gas, 400 W RF is applied to the target, and the carbon powder and balls are applied. On the other hand, when sputtering was performed for 30 minutes while applying vibration by a vibrator, the carbon powder increased in weight to 1.66 g, and the catalyst was made of 0.66 g of an alloy of Pt / each additive element (the MII). Material deposited on the carbon. This corresponds to the weight ratio of 40 wt% Pt-supported carbon.

  Next, a mixed liquid obtained by kneading a binder made of Teflon (registered trademark) and carbon (without platinum) on the carbon sheet is applied to a thickness of 20 μm after drying, and this is applied to the soaking prevention layer. It was.

Further, each carbon powder carrying the Pt / additive element (MII) alloy obtained by the above method was kneaded with perfluorosulfonic acid as a binder and nPA (normal propyl alcohol) as an organic solvent, This mixed solution was applied and dried on a soaking prevention layer formed on a carbon sheet so that the coating thickness after drying was 20 μm, thereby obtaining each gas diffusible catalyst electrode. These gas diffusive catalyst electrodes were arranged on both sides of an ion exchange membrane (perfluorosulfonic acid) to produce a fuel cell as shown in FIG. 8, and the initial output and the output after 200 hours of operation were measured. The measurement results are also shown in Table 1 below. The initial output (unit mW / cm ² ) of the fuel cell using the gas diffusing catalyst electrode to which the additive element as MII was not added was set to 100% as a relative value, and this was set as a reference value.

Example 2
Except that the ball as the vibration amplification means was not used, the following table was used as a target for Pt having a particle diameter of 100 mm as shown in FIG. Sputtering was performed using a material in which 3 at% of each additive element as MII shown in 2 was introduced, and each gas diffusible catalyst electrode was produced. These gas diffusive catalyst electrodes were arranged on both sides of the ion exchange membrane to produce a fuel cell as shown in FIG. 8, and the initial output and the output after 200 hours of operation were measured. The measurement results are also shown in Table 2 below. In Example 1, the initial output (unit mW / cm ² ) of the fuel cell using the gas diffusive catalyst electrode to which the additive element as MII was not added was set to 100% as a relative value, and this was the reference value. It was.

Example 3
Except that the ball as the vibration amplification means was not used and was not vibrated, the target was Pt having a particle diameter of 100 mm as MI as shown in FIG. On the other hand, sputtering was performed using a material in which 3 at% of each additive element as MII shown in Table 3 below was introduced, and each gas diffusible catalyst electrode was produced. These gas diffusive catalyst electrodes were arranged on both sides of the ion exchange membrane to produce a fuel cell as shown in FIG. 8, and the initial output and the output after 200 hours of operation were measured. The measurement results are also shown in Table 3 below. In Example 1, the initial output (unit mW / cm ² ) of the fuel cell using the gas diffusive catalyst electrode to which the additive element as MII was not added was set to 100% as a relative value, and this was the reference value. It was.

  As apparent from the above, Pt as MI and each additive element as MII could be alloyed by the physical vapor deposition such as sputtering. Further, the gas diffusive catalyst electrode according to the present invention has the catalyst material made of an alloy of Pt as MI and each additive element as MII attached to the surface of the conductive powder by sputtering. Since the conductive catalyst particles according to the present invention are contained, internal self-diffusion of the Pt crystal lattice in the catalyst material is prevented, and sintering is difficult to occur, which is longer than in the case of only Pt. Good output could be maintained over time.

  In addition, if the catalyst material is adhered to the surface of the carbon powder while vibrating the carbon powder as the conductive powder, the carbon powder is compared with the case where the catalyst material is adhered without being vibrated. Thus, the catalyst material can be more uniformly attached, and the output is further improved.

  Further, a carbon powder as the conductive powder and a ball as the vibration amplifying means are arranged on the vibration surface, and the catalyst material can be adhered to the surface of the carbon powder while vibrating them. For example, the carbon powder is further vibrated and no longer stays at one place on the vibration surface as compared with the case where the ball is vibrated without adding the ball. Therefore, the catalyst material can be more uniformly adhered to the entire carbon powder disposed in the container, and the output is further improved.

  Here, the MII includes Cu, Zr, Ti, V, Nb, Ta, W, Ga, Ge, Si, Re, Os, Pb, including each additive element shown in Table 1, Table 2, and Table 3. Even when at least one selected from the group consisting of Bi, Sb, Mo, O, N, F, C, Zn, In and rare earth elements was introduced, the same effect as described above was obtained.

Example 4
As shown in Table 4 below, fuel cells as shown in FIG. 8 were produced in the same manner as in Example 1 except that the kind of additive element as MII and the amount of addition were changed. The results of measuring the initial output of each fuel cell and the output after 200 hours of operation are also shown in Table 4 and FIG. The initial output (unit mW / cm ² ) of the fuel cell using the gas diffusing catalyst electrode to which the additive element as MII was not added was set to 100% as a relative value, and this was set as a reference value.

  As is apparent from Table 4 and FIG. 12, by specifying the addition amount of each additive element as MII as 0.5 at% or more, a more effective anti-sintering effect can be obtained and a better catalyst It can have activity and can maintain a high output for a long time. If it is less than 0.5 at%, the amount of MII is too small, and the sintering preventing effect may be reduced.

Example 5
A fuel cell as shown in FIG. 8 was produced in the same manner as in Example 1 except that Hf belonging to MII ′ was used as MII and the amount of Hf added was changed as shown in Table 5 below. did. The results of measuring the initial output of each fuel cell and the output after 200 hours of operation are also shown in Table 5 and FIG. In addition, the initial output (unit mW / cm ² ) of the fuel cell using the gas diffusive catalyst electrode to which Hf was not added was set to 100% as a relative value, and this was set as a reference value.

  As is clear from Table 5 and FIG. 13, when Hf belonging to MII ′ is used as the MII, by specifying the addition amount as 20 at% or less, a further excellent anti-sintering effect can be obtained. And good output was obtained. When it exceeded 20 at%, sintering could be prevented, but the output was sometimes lowered due to an excessive amount of Hf added.

  Moreover, in Example 5, although the example which uses Hf which belongs to said MII 'was shown as said MII, Co, Ni, Cr, Al, Cu, Mo, W, O, N, F including Hf were shown. Similar results were obtained using at least one selected from the group consisting of C and C.

Example 6
Example 1 except that a mixture of Fe belonging to MII ′ and Hf belonging to MII ″ was used as MII, and the addition amount of each additive element was changed as shown in Tables 6 and 7 below. The fuel cells as shown in Fig. 8 were produced in the same manner as in Fig. 8. The results of measuring the initial output of each fuel cell and the output after 200 hours of operation are shown in Tables 6 and 14, Tables 7 and 15 below. The initial output (unit: mW / cm ² ) of a fuel cell using a gas diffusible catalyst electrode to which a mixture of Fe belonging to MII ′ and Hf belonging to MII ″ was not added is a relative value. And 100%, and this was taken as the reference value.

As is clear from the above, even when a mixture (Fe _b -Hf _c ) composed of, for example, Fe as MII ′ and Hf as MII ″ is used, each additive element is used alone. The same excellent anti-sintering effect and output can be obtained, and by specifying the addition amount of the mixture in the range of 0.5 at% ≦ b + c ≦ 60 at%, it has further excellent catalytic ability and more output In addition, since it was possible to more effectively prevent the occurrence of sintering, it was possible to maintain a high output for a longer time, as can be seen from Table 6 and FIG. When the value is less than 0.5 at%, the amount of MII ′ and MII ″ added is too small, and the sintering preventing effect may be reduced. Further, as apparent from Table 7 and FIG. 15, when the amount exceeds 60 at%, the amount of MII ′ and MII ″ added is too large, so that the catalytic action tends to decrease and the output may decrease.

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

  In Example 6, the MII ′ includes at least one selected from the group consisting of Co, Ni, Cr, Al, Sn, Cu, Mo, W, O, N, F, and C, including the above additive elements. Species can be used, and the MII ″ includes Zr, Ti, V, Nb, Ta, Ga, Ge, Si, Re, Os, Pb, Bi, Sb, Mn, and rare earth elements including the above-described additive elements. At least one selected from the group consisting of can be used.

Further, although Pt is used as the MI, at least one selected from noble metal elements such as Ir, Pd, Rh, Au, and Ru can be used, and the carbon is used as the conductive powder. Although powder was used, the ITO, SnO ₂ or the like can also be used.

  Further, although the ball is used as the vibration amplifying means, a substantially spiral part as shown in FIG. 5, a substantially concentric part as shown in FIG. 6, or a substantially folded shape as shown in FIG. These parts may be used, and excellent results equivalent to those in Examples 1 to 6 were obtained.

  Furthermore, although the said fuel cell using the gas diffusible catalyst electrode based on this invention was demonstrated, the said gas diffusable catalyst electrode is applicable also to the said hydrogen production apparatus which is a reverse reaction of the said fuel cell.

  The gas diffusive catalyst electrode using the conductive catalyst particles of the present invention is useful for a fuel cell and a hydrogen production apparatus.

It is the schematic sectional drawing (A) of the apparatus which can be used for the manufacturing method of the electroconductive catalyst particle based on this invention, and the top view (B) of a target. It is a schematic sectional drawing (A), (B), (C) which shows various electroconductive catalyst particles equally. FIG. 2 is a partially enlarged schematic view of a container in an apparatus that can be used in the method for producing conductive catalyst particles. 2 is a partially enlarged schematic cross-sectional view of the apparatus. FIG. It is the schematic plan view (A) of the vibration apparatus used for an apparatus, and its VB-VB sectional view (B). FIG. 6 is a schematic plan view (A) of another vibration device and a sectional view taken along the line VIB-VIB (B). FIG. 6 is a schematic plan view (A) of still another vibration device and a sectional view taken along the line VIIB-VIIB (B). It is a schematic block diagram of the fuel cell using the gas diffusible catalyst electrode based on this invention. It is a schematic block diagram of the hydrogen production apparatus using the gas diffusible catalyst electrode. 1 is a structural diagram of a polyhydroxylated fullerene that is an example of a fullerene derivative that can be used in an embodiment of the present invention. It is a schematic diagram which shows the example of a fullerene derivative similarly. It is a figure which shows the relationship between the addition amount of MII and the output after a 200-hour driving | operation by the Example based on this invention. FIG. 6 is a graph showing the relationship between the amount of MII ″ added and the output after 200 hours of operation. FIG. 4 is a graph showing the relationship between the amount of MII added consisting of a mixture of MII ′ and MII ″ and the output after 200 hours of operation. FIG. 4 is a graph showing the relationship between the amount of MII added consisting of a mixture of MII ′ and MII ″ and the output after 200 hours of operation. It is a schematic sectional drawing which shows the electroconductive catalyst particle obtained by carrying | supporting platinum on carbon powder with the conventional manufacturing method. It is a schematic sectional drawing of the manufacturing apparatus of the electroconductive catalyst particle by prior invention (Unexamined-Japanese-Patent No. 2002-110175). FIG. 2 is a schematic cross-sectional view of conductive catalyst particles.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Conductive powder (carbon powder etc.), 4 ... Target, 5 ... Ball, 6 ... Container,
7 ... Vibrating surface, 8 ... Vibrator (coil type), 9 ... Vibrating device, 11 ... Ion conductor,
12 ... MI, 13 ... MII, 14 ... catalyst material made of MI / MII alloy,
15: substantially spiral vibration amplifying means, 16: substantially concentric vibration amplifying means,
17 ... substantially folded vibration amplification means, 18, 18 '... catalyst layer,
19, 19 '... gas permeable current collector, 20, 20' ... ion conduction part, 21, 23 ... terminal,
22, 22 '... negative electrode, 24, 24' ... positive electrode, 25 ... H ₂ flow passage, 26 ... O ₂ passage

Claims (29)

  On the surface of the conductive powder, MI (where MI is at least one selected from noble metal elements consisting of Pt, Ir, Pd, Rh, Au, or Ru) and MII (where MII is Co, Ni, Cr, Al, Cu, Hf, Zr, Ti, V, Nb, Ta, W, Ga, Ge, Si, Re, Os, Pb, Bi, Sb, Mo, O, N, F, C, Zn, Conductive catalyst particles to which a catalyst material made of an alloy with In and at least one selected from rare earth elements is attached. The catalyst material is an MI-MII'-MII "alloy (where MI is at least one selected from noble metal elements consisting of Pt, Ir, Pd, Rh, Au, or Ru. MII 'is Fe, Co, It is at least one selected from Ni, Cr, Al, Sn, Cu, Mo, W, O, N, F and C. MII "is Hf, Zr, Ti, V, Nb, Ta, Ga, Ge, And at least one selected from Si, Re, Os, Pb, Bi, Sb, Mn, and rare earth elements.) When the composition is MI _a −MII ′ _b −MII ″ _c , a + b + c = 100 at% 0.5 at% ≦ b + c ≦ 60 at%, b ≦ 60 at%, c ≦ 20 at%.   The conductive catalyst particle according to claim 1 or 2, wherein the catalyst material is attached by physical vapor deposition.   The conductive catalyst particle according to claim 3, wherein the physical vapor deposition method is a sputtering method using the MI and MII as targets.   The conductive catalyst particle according to claim 3, wherein the physical vapor deposition method is a pulse laser deposition method.   The conductive catalyst particle according to claim 1 or 2, wherein an ionic conductor is attached to a surface of the conductive powder, and further, the catalyst material is attached to a surface of the ionic conductor.   The conductive catalyst particle according to claim 1 or 2, wherein the amount of the catalyst material attached is 10 to 1000% by weight with respect to the conductive powder. 3. The conductive catalyst particle according to claim 1, wherein an electric resistance of the conductive powder is 10 ⁻³ Ω · m or less. Wherein the conductive powder is carbon, ITO (Indium tin oxide: a conductive oxide doped with tin indium oxide) and at least one of SnO _2, conductive catalyst according to claim 1 or 2 particle. The conductive catalyst particle according to claim 1, wherein the conductive powder is carbon having a specific surface area of 300 m ² / g or more.   The electroconductive catalyst particle according to claim 1 or 2, wherein the electroconductive powder is carbon having an oil absorption of 200 ml / 100 g or more.   A gas diffusive catalyst electrode containing the conductive catalyst particles according to any one of claims 1 to 11.   The gas diffusive catalyst electrode according to claim 12, wherein the conductive catalyst particles are bound with a resin.   The gas diffusive catalyst electrode according to claim 12, wherein the conductive catalyst particles are attached on a current collector.   An electrochemistry comprising at least two electrodes and an ionic conductor sandwiched between the electrodes, wherein the gas diffusing catalyst electrode according to claim 12 constitutes at least one of the electrodes. device.   The electrochemical device according to claim 15 configured as a fuel cell.   The electrochemical device according to claim 15, which is configured as a hydrogen production apparatus.   MI (where MI is at least one selected from the precious metal elements consisting of Pt, Ir, Pd, Rh, Au or Ru) and MII (MII is Co, Ni, Cr, Al, Cu, Hf, At least one selected from Zr, Ti, V, Nb, Ta, W, Ga, Ge, Si, Re, Os, Pb, Bi, Sb, Mo, O, N, F, C, Zn, In and rare earth elements Are deposited on the surface of the conductive powder by physical vapor deposition, thereby obtaining conductive catalyst particles in which a catalyst material made of an alloy of MI and MII is adhered. For producing conductive catalyst particles.   19. The method for producing conductive catalyst particles according to claim 18, wherein the conductive powder is vibrated when the MI and the MII are attached to the surface of the conductive powder by the physical vapor deposition method.   The conductivity according to claim 19, wherein the M I and the M II are attached to the surface of the conductive powder by the physical vapor deposition while vibrating the conductive powder and the vibration amplifying means. A method for producing catalyst particles.   21. The method for producing conductive catalyst particles according to claim 20, wherein a ball is used as the vibration amplification means, the conductive powder and the ball are mixed and placed in the same container, and the vibration is applied.   The method for producing conductive catalyst particles according to claim 21, wherein the balls are ceramic or metal balls having a diameter of 1 to 10 mm.   As the vibration amplifying means, a part that is substantially planar and formed in a substantially spiral, substantially concentric or substantially folded pattern is used, and at least a part of the part is not fixed to the container. The method for producing conductive catalyst particles according to claim 20, wherein the conductive powder is disposed on the component and the vibration is applied to the component.   The method for producing conductive catalyst particles according to claim 23, wherein the part formed in a substantially spiral, substantially concentric or substantially folded pattern is a metal wire having a diameter of 1 to 10 mm.   24. The conductivity according to claim 23, wherein the outer diameter of the component formed in a substantially spiral, substantially concentric or substantially folded pattern is 5 mm smaller than the inner diameter of the container, and the pattern pitch is 5 to 15 mm. A method for producing catalyst particles.   The method for producing conductive catalyst particles according to claim 20, wherein a thickness or a diameter of the vibration amplifying means is 10 to 70% with respect to a layer thickness formed by the conductive powder.   The method for producing conductive catalyst particles according to claim 20, wherein an area ratio of the vibration amplifying unit to a distribution region of the conductive powder is 30 to 80%.   The method for producing conductive catalyst particles according to claim 19, wherein the vibration frequency is 5 to 200 Hz.   The method for producing conductive catalyst particles according to claim 19, wherein the amplitude of the vibration is ± (0.5 to 20) mm.

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