WO2008018619A1

WO2008018619A1 - Polygonal barrel sputtering apparatus, surface modified carbon material and method for manufacturing the surface modified carbon material

Info

Publication number: WO2008018619A1
Application number: PCT/JP2007/065885
Authority: WO
Inventors: Takayuki Abe; Yuuji Honda; Hironari Yamamoto
Original assignee: Youtec Co., Ltd.; Nippon Pillar Packing Co., Ltd.
Priority date: 2006-08-08
Filing date: 2007-08-08
Publication date: 2008-02-14
Also published as: JP2008038218A

Abstract

This invention provides a polygonal barrel sputtering apparatus which can support a number of catalyst fine particles onto the outer surface of a carbon carrier, and a carbon supported catalyst and a method for manufacturing the carbon supported catalyst. The polygonal barrel sputtering apparatus comprises a vacuum vessel(1) of which the internal shape of the cross section substantially parallel to the gravitational direction is polygonal, a dispersing member, which is placed within the vacuum vessel (1), for dispersing secondary particles produced by the aggregation of primary particles of the carbon carrier (3) into primary particles or secondary particles which are smaller than the original secondary particles, a rotating mechanism for rotating the vacuum vessel around a rotation axis substantially vertical to the above cross section, and a sputtering target (2) disposed within the vacuum vessel (1). The polygonal barrel sputtering apparatus is characterized in that sputtering is carried out while carrying out rotation or pendulum operation of the vacuum vessel (1) with the rotating mechanism to agitate or rotate the carbon carrier (3) within the vacuum vessel to disperse the secondary particles of the carbon carrier (3) with the aid of the dispersing member, whereby fine particles or a thin film is supported on the surface of the carbon carrier (3).

Description

Description Polygonal Barrel Sputtering Equipment, Surface-Modified Carbon Material and Manufacturing Method 1. Technical Field

The present invention relates to a polygonal barrel sputtering apparatus capable of supporting many fine particles or thin films on the outer surface of a carbon support, a surface-modified carbon material, and a method for producing the same.

2. Background technology

A fuel cell is a new power generation system that converts the energy produced by the electrochemical reaction of fuel gas and oxidant gas directly into electrical energy.

Molten carbonate electrolyte fuel cell operating at (500 to 700 ° C), Phosphate electrolyte fuel cell operating near 200 ° C, Alkaline electrolyte fuel cell and polymer operating at room temperature or below about 100 ° C It is classified as an electrolyte fuel cell.

As the polymer electrolyte fuel cell, hydrogen exchange membrane fuel cell using hydrogen gas as fuel (Proton Ex change Membrane Fuel 1 Cell: PEMFC) and liquid methanol as direct fuel to the anode. There are direct methanol fuel cells (D irect Me thano 1 Fuel Cell: DMF C) that are supplied and used.

In order to increase the energy density of fuel cells and improve output density and output voltage, research is actively conducted on electrodes, fuels, and electrolyte membranes. In particular, we will improve the activity of catalysts used in electrodes. There are many attempts to do this. In general, Pt, Pt, and Pt alloys are widely used as catalysts for PEMFC and DMFC. To ensure price competitiveness, however, the amount of catalyst used may be reduced. preferable. As a method of reducing the amount of catalyst while maintaining or increasing the performance of the fuel cell, a conductive carbon material having a large specific surface area is used as a support, and Pt and the like are dispersed in a fine particle state to form catalytic metal particles. Electrochemical activity table Five

2 The method of increasing the area is used.

The activity of the catalyst improves as the electrochemically active surface area of the catalyst increases. In order to increase the active surface area, the amount of the supported catalyst can be simply increased. In this case, the amount of the carbon support used increases, so the thickness of the electrode also increases. For this reason, problems such as an increase in the internal resistance of the electrode and difficulty in forming the electrode occur. Therefore, it is required to increase the concentration of the supported catalyst while keeping the amount of the carrier used constant.

Hereinafter, a conventional method for producing a surface-modified carbon material will be described.

The process includes impregnating a carbon nanotube, which is a carbon support, with a solvent and platinum precursor, which is finally supported as a catalyst metal, at least twice, and the catalyst metal precursor is impregnated between the impregnation stages. Drying the carbon support and reducing it.

More specifically, the method for producing a surface-modified carbon material includes: (a) impregnating a carbon support with a metal precursor solution in which a part of a precursor of platinum, which is a catalyst metal that is finally supported, is mixed. (B) a first drying step for drying the carbon support impregnated with the catalyst metal precursor; and (c) a first reduction for reducing the carbon support impregnated with the catalyst metal precursor. A reduction step, and (d) a second impregnation step in which the carbon support preliminarily impregnated with catalyst metal particles is impregnated again with a metal precursor solution in which the solvent and the remainder of the catalyst metal precursor to be finally supported are mixed. (E) a second drying step of drying the carbon support impregnated with the catalyst metal precursor and the catalyst metal particles, and (f) the catalyst metal precursor and the catalyst metal particles impregnated Including a second reduction stage for reducing the carbon support There (for example, Japanese 2 0 0 5 1 0 8 8 3 8 No. 2 7 of the publication, the second 9, Section 3 0 paragraph). 3. Disclosure of the Invention

In the conventional method for producing a surface-modified carbon material, an impregnation method is used as a method for supporting platinum as a catalyst metal on carbon nanotubes. In this impregnation method, carbon nanotubes are impregnated with a metal precursor solution as described above. Therefore, the metal precursor solution is carbon nanotube

It is sucked in by the effect, and finally a lot of platinum is carried in the tube, not on the outside of the carbon nanotube. When a large amount of platinum is supported on the inside of the carbon nano tube from the outside, much of the platinum in the tube is not used as an electrocatalyst, so much of the platinum in the tube is wasted. Therefore, development of a method for supporting a large number of catalyst fine particles on the outer surface of a carbon support such as a carbon nanotube is required.

The present invention has been made in consideration of the above-described circumstances, and its purpose is to provide a polygonal barrel sputtering apparatus, a surface-modified carbon material and a method for producing the same that can carry a large number of fine particles or thin films on the outer surface of a carbon support. It is to provide.

In order to solve the above problems, we focused on the sputtering method, which is one of the physical vapor deposition methods that does not cause the effect of the chirality. This method is considered to be very versatile for reasons such as selecting a carrier, modifying the surface of the carrier from metal to inorganic, and reducing the environmental burden. This time, we invented the polygonal parallel sputtering method. This method is a method in which a large number of fine particles or thin films are supported on the outer surface of the carbon support by rotating or rotating the polygonal pellet in which the carbon support is contained.

This will be specifically described below.

The polygonal barrel sputtering apparatus according to the present invention is a vacuum container that contains a carbon carrier, and a vacuum container having a polygonal cross-sectional shape substantially parallel to the direction of gravity, and is placed in the vacuum container, A dispersion member that disperses secondary particles formed by agglomeration of primary particles of carbon support into secondary particles that are smaller than the primary particles or the original secondary particles;

A rotation mechanism that rotates the vacuum vessel about a direction substantially perpendicular to the cross section;

A sputtering target disposed in the vacuum vessel;

Comprising

Rotating operation for rotating the vacuum vessel in one direction using the rotating mechanism, or Rotating in one direction and then rotating in the opposite direction

By performing sputtering while dispersing or dispersing secondary particles of the carbon support by the dispersing member while stirring or rotating the carbon support in the vacuum vessel, fine particles or thin films are formed on the surface of the carbon support. It is characterized by being supported.

The pendulum operation is an operation that rotates in one direction at a rotation angle of 180 ° or less or more than 180 °, and in the opposite direction to rotate at a rotation angle of 180 ° or less or more than 180 °. It is an operation to repeat.

According to the above-mentioned polygonal parel sputtering apparatus, fine particles or thin films are supported on the surface of the carbon support by sputtering. Since sputtering has directivity and does not have a chiral effect, many fine particles or thin films can be carried on the outer surface of the carbon support.

In addition, the carbon carrier itself and the dispersion member are both rotated by rotating or pendulum-moving the vacuum vessel itself with a substantially vertical direction (that is, substantially horizontal direction) as a rotation axis with respect to a cross section substantially parallel to the direction of gravity. Furthermore, by making the cross-sectional shape of the inner part of the vacuum vessel polygonal, the carbon carrier and the dispersion member can be dropped periodically by gravity, and the carbon carrier can collide with the inner wall of the vacuum vessel. . For this reason, the stirring efficiency can be drastically improved, aggregation of the carbon support can be prevented, and in addition, the aggregated carbon support can be stirred while being dispersed by the dispersing member. That is, the stirring by the rotation operation or the pendulum operation and the dispersion of the aggregated carbon support can be performed simultaneously and effectively. Therefore, fine particles having a relatively small particle size can be supported on the carbon support.

In the polygonal barrel sputtering apparatus according to the present invention, the dispersion member preferably includes at least one of a powdery substance, a rod-like substance, a small piece, a spherical substance, and a substance having a plurality of protrusions.

The polygonal barrel sputtering apparatus according to the present invention may further include a vibrator that applies vibration to the vacuum vessel. This makes it possible to prevent aggregation more effectively. Also, in the polygonal barrel sputtering apparatus according to the present invention

It is also possible to further include a heater for heating the carbon support. For example, when the inside of the vacuum vessel is evacuated, by heating the vacuum vessel with a heater, moisture adsorbed in the vacuum vessel and on the surface of the carbon support can be vaporized and exhausted. Therefore, since water can be removed from the inside of the vacuum container, aggregation of the carbon support can be prevented more effectively.

In the method for producing a surface-modified carbon material according to the present invention, the carbon carrier and the primary particles of the carbon carrier are aggregated in a vacuum vessel having a polygonal internal shape in a cross section substantially parallel to the direction of gravity. Containing a dispersing member that disperses the resulting secondary particles into primary particles or secondary particles smaller than the original secondary particles;

By performing a pendulum operation that repeats a rotation operation in which the vacuum vessel is rotated in one direction about a direction substantially perpendicular to the cross-section, or a rotation in the opposite direction after rotating in one direction, the vacuum vessel Sputtering is performed while dispersing the secondary particles of the carbon support by the dispersion member while stirring or rotating the carbon support inside, thereby supporting fine particles or a thin film on the surface of the carbon support. .

In the method for producing a surface-modified carbon material according to the present invention, the carbon support may be a single-wall carbon nanotubes (SWNT) _Λ double-wall carbon nanotubes (DWNT) multi-layer carbon nanotube. Multi-wall carbon nanotubes (MWNT), carbon nanophones, carbon nanocoils, cup-stacked carbon nanotubes, bamboo-shaped carbon nanotubes, vapor-grown carbon fibers (VGCF) _N- carbon nanofibers It is preferably at least one of graphite nanofibers, fullerenes, car pump racks, and carbon single crystals. The surface-modified carbon material according to the present invention rotates a vacuum vessel having a polygonal cross-sectional shape in one direction with a substantially vertical direction as a rotation axis with respect to the cross-section, or rotates in one direction. After repeating the operation of rotating in the opposite direction, the carbon carrier in the vacuum vessel is agitated or rotated by performing a pendulum operation. By performing sputtering while rolling, the charcoal

Is characterized in that a thin film is supported.

In the surface-modified carbon material according to the present invention, it is preferable that the carbon support is a carbon nanotube, and more fine particles or thin films are supported on the outer surface of the carbon nanotube than in the tube. In the surface-modified carbon material according to the present invention, it is preferable that approximately 100% of the fine particles or thin film supported on the carbon nanotube is supported on the outer surface of the tube.

As described above, according to the present invention, it is possible to provide a multi-barrel sputtering apparatus, a carbon-supported catalyst, and a method for producing the same that can support a large number of catalyst fine particles on the outer surface of a carbon support.

4. Brief description of the drawings

FIG. 1 is a configuration diagram showing an outline of a polygonal barrel sputtering apparatus according to the first embodiment.

FIG. 2 is a photograph of the carbon-supported catalyst according to Embodiment 1 observed with an electron microscope.

FIG. 3 is a photograph of the carbon-supported catalyst according to Embodiment 1 observed with an electron microscope.

FIG. 4 is a graph showing the particle size distribution of Pt fine particles supported on the carbon supported catalyst shown in FIG.

Fig. 5 (A) shows the results of EDX analysis of the carbon nanotubes before supporting Pt. Fig. 5 (B) shows the carbon-supported catalyst according to Embodiment 1 as EDX. Therefore, it is a figure which shows the result analyzed.

FIG. 6 is a diagram showing the results of analyzing the carbon-supported catalyst according to Embodiment 1 by XRD.

FIG. 7 is a diagram showing the result of XRF analysis of the carbon-supported catalyst according to the first embodiment. Figure 8 shows the carbon supported catalyst according to the second embodiment.

It is an EM photograph.

FIG. 9 is a TEM photograph of the carbon-supported catalyst according to Embodiment 2 observed with an electron microscope. ,

FIG. 10 is a graph showing the particle size distribution of Pt fine particles supported on the carbon supported catalyst shown in FIG.

FIG. 11 is a diagram showing a result of analyzing a carbon-supported catalyst according to Embodiment 2 by XRD.

FIG. 12 is a diagram showing the results of analyzing the carbon-supported catalyst according to Embodiment 2 by XRF.

(Explanation of symbols)

1 ... Vacuum container

1 a… Cylindrical part

1 b ... Hexagonal type

2… Target

3… Carbon support

4 to 9 ... Piping

1 0… Turbo molecular pump (TMP)

1 1 ... Pump (RP)

1 2-14 ... 1st-3rd valve

1 5… Nitrogen gas introduction mechanism

1 6… Argon gas introduction mechanism

1 7… Heater

1 8 ... Piplator

1 9… Pressure gauge

5. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)

FIG. 1 is a configuration diagram showing an outline of a polygonal barrel sputtering apparatus according to Embodiment 1 of the present invention. In this multi-barrel sputtering apparatus, catalyst fine particles having a relatively small particle diameter (an example of particle diameter; 1 to 100 nm, more preferably 1 to 3 nm) are applied to the surface of a carbon support 3 made of carbon nanotubes. It is a device for carrying. Also, with this device, the particle size of the supported platinum fine particles can be reduced to 1 to 100 nm by controlling sputtering conditions such as argon flow rate (total pressure), high frequency output, sputtering time, and temperature. It can be easily controlled within a range.

In this embodiment, the catalyst fine particles are supported on the surface of the carbon support 3 made of carbon nanotubes, but the present invention is not limited to this, and the catalyst fine particles are supported on the surface of the carbon support other than the carbon nanotubes. It is also possible to make it. Specific examples of carbon carriers include single-walled carbon nanotubes, double-walled carbon nanotubes, multi-walled carbon nanotubes, carbon nanohorns, carbon nanocoils, cup-stacked carbon nanotubes, bamboo-shaped carbon nanotubes, vapor-grown carbon fibers, carbon Nanofibers, graphite nanofibers, fullerenes, carbon black and carbon single crystals.

The polygonal barrel sputtering apparatus has a vacuum container 1 for supporting catalyst fine particles on a carbon support 3, and this vacuum container 1 has a cylindrical portion 1a having a diameter of 20 O mm and a cross section installed in the inside thereof. Hexagonal barrel (hexagonal barrel) 1 b. The cross section shown here is a cross section substantially parallel to the direction of gravity. In this embodiment, the hexagonal barrel 1b is used. However, the present invention is not limited to this, and a polygonal barrel other than the hexagon can also be used.

In the hexagonal barrel lb, secondary particles (size: for example, 100 nm to l 0 O mm) formed by agglomeration of primary particles of the carbon support 3 by moisture, electrostatic force, intermolecular force, etc. Disperse again into primary particles or secondary particles smaller than the original secondary particles A dispersion member (not shown) is inserted. This minute

The carbon support 3 aggregated and collected is dispersed, and examples thereof include powdery substances, rod-like substances, small pieces, spherical substances, and substances having a plurality of protrusions.

The size of the powdery substance is, for example, about 0 · l to 5 mm, and specific examples include sand and alumina powder.

In addition, the rod-like substance is a rod-like substance having a size of, for example, a length of 1 to 5 Omm and a thickness of about 0.1 mm to 1 Omm. Specific examples include a nail, a wire, a square bar, and a port. Can be mentioned.

The small piece has a size of, for example, about 1 to 10 Omm, and specific examples of the material include metals and resins.

In addition, the spherical substance has a diameter of, for example, about 1 to 5 Omm. Specific examples include iron balls, plastic balls, BB bullets, beads, and the like. The substance having a plurality of protrusions has a size of about 10 to 5 Omm and a large number of protrusions, and specific examples thereof include demon nuts.

The vacuum vessel 1 is provided with a rotation mechanism (not shown). By this rotation mechanism, the hexagonal barrel 1 b is rotated in one direction (in the direction of the arrow), or after being rotated in one direction. By performing a pendulum operation that repeats the operation of rotating in the opposite direction (the direction opposite to the arrow), the carbon support 3 in the hexagonal barrel 1b is stirred or rotated while the carbon support 2 The supporting treatment is performed while the next particles are dispersed.

The size of the original secondary particle is, for example, 1 00 ηπ! ~ 10 Omm. In addition, the pendulum operation includes, of course, an operation that repeats the operation of rotating at a rotation angle of 1 80 ° or less in one direction and rotating at a rotation angle of 1 80 ° or less in the opposite direction. This includes the operation of rotating at a rotation angle of more than 80 ° (eg, a rotation angle of 720 °) and rotating in the opposite direction at a rotation angle of more than 1 80 ° (eg, a rotation angle of 720 °). Hexagonal parel is rotated by the rotating mechanism I

An axis parallel to the direction (perpendicular to the direction of gravity). Further, a sputtering target 2 made of Pt is disposed on the central axis of the cylinder in the vacuum vessel 1, and the target 2 is configured so that the angle can be freely changed. As a result, when carrying the supporting process while rotating the hexagonal barrel 1b, the target 2 can be directed in the direction in which the carbon carrier 3 is located, thereby increasing the sputtering efficiency. In this embodiment, a Pt target is used. However, a material other than Pt (for example, Pd, Ni, etc.) can also be supported on the carbon support, in which case it is supported. A target made of material will be used.

One end of a pipe 4 is connected to the vacuum vessel 1, and one side of the first valve 12 is connected to the other end of the pipe 4. One end of the pipe 5 is connected to the other side of the first valve 12, and the other end of the pipe 5 is connected to the intake side of the turbo molecular pump (TMP) 10. The exhaust side of the turbo molecular pump 10 is connected to one end of the pipe 6, and the other end of the pipe 6 is connected to one side of the second pulp 13. The other side of the second pulp 13 is connected to one end of the pipe 7, and the other end of the pipe 7 is connected to the pump (R P) 11. The pipe 4 is connected to one end of the pipe 8, and the other end of the pipe 8 is connected to one side of the third pulp 14. The other side of the third pulp 14 is connected to one end of the pipe 9, and the other end of the pipe 9 is connected to the pipe 7.

This apparatus is provided with a heater 17 for heating the carbon carrier 3 in the vacuum vessel 1. The apparatus also includes a vibrator 18 for applying vibration to the carbon carrier 3 in the vacuum vessel 1. The apparatus also includes a pressure gauge 19 that measures the internal pressure of the vacuum vessel 1. The apparatus also includes a nitrogen gas introduction mechanism 15 for introducing nitrogen gas into the vacuum vessel 1 and an argon gas introduction mechanism 16 for introducing argon gas into the vacuum vessel 1. In addition, this apparatus includes a high-frequency application mechanism (not shown) that applies a high frequency between the target 2 and the hexagonal barrel 1 b. Next, charcoal using the above polygonal barrel sputtering apparatus

A method for manufacturing a polygonal barrel sputtering method and a carbon-supported catalyst will be described.

First, about 0.03 gram of carbon support 3 is introduced into the hexagonal barrel 1b. As the carbon support 3, CNI (registered trademark) Buckytubes single-walled carbon nanotubes (SWNT) were used. In addition, nails were used as dispersion members. Pt was used for target 2. In this embodiment, the carbon nano tube is used. However, the present invention is not limited to this, and it is also possible to use a carbon support made of other materials. If this polygonal barrel sputtering method is used, fine particles can be supported on a wide range of carbon carriers.

Next, a high vacuum state was created in the hexagonal barrel 1 b using a turbo molecular pump 10, and the inside of the hexagonal barrel was depressurized to 8 × 10 — ⁴ Pa. Thereafter, an inert gas such as argon or nitrogen is introduced into the hexagonal barrel 1 b by the argon gas supply mechanism 16 or the nitrogen gas supply mechanism 15. At this time, the pressure in the hexagonal barrel is about 0.8 Pa. In some cases, a mixed gas of oxygen and hydrogen may be introduced into the hexagonal parallel 1b 內. Here, about 90 ccm of argon gas is introduced into the hexagonal barrel 1 b, and the argon pressure is about 30 Pa. Then, by rotating the hexagonal barrel 1b for 30 minutes at an angle of 75 ° and 3.5 rpm by a rotating mechanism, the nail that is a member to be agitated with the carbon nanotubes 3 in the hexagonal barrel 1b is agitated. Rotate to disperse the aggregated carbon nanotubes 3. At the same time, a high frequency output of 50 W, for example, is applied between the target 2 and the hexagonal barrel 1 b by the high frequency application mechanism, so that Pt is sputter deposited on the surface of the carbon nanotube 3 at room temperature. At that time, the target is directed in the direction in which the carbon nanotube is located. In this way, Pt fine particles can be supported on the surface of the carbon nanotube 3. It should be noted that here, the force with which the pendulum movement is performed at an angle of 75 ° on the hexagonal barrel 1 b is not limited to this, and it is possible to change the angle of the pendulum movement to another angle. It is also possible to perform rotation instead of pendulum movement It is. Here, the rotation speed of the pendulum movement is 3

It is also possible to increase the rotation speed of the pendulum operation to about 20 rpm. Here, the high-frequency output is 5 OW, but the high-frequency output can be increased to about 50 OW. Here, the temperature at which the Pt fine particles are supported is room temperature, but the temperature can be increased to about 600 ° C. According to the first embodiment, the carbon nanotube itself can be rotated and stirred together with the nail by causing the hexagonal barrel itself to perform a pendulum operation or a rotation operation. Can be dropped regularly. For this reason, the stirring efficiency can be drastically improved, and aggregation due to moisture, electrostatic force, and intermolecular force can be prevented. In addition, since the carbon nanotubes are stirred together with the nail, the aggregated carbon nanotubes are removed by the nail. It can be stirred while being dispersed. That is, stirring by rotation and dispersion of the aggregated carbon nanotubes can be performed simultaneously and effectively. Therefore, Pt fine particles having a relatively small particle size can be supported on the carbon nanotube 3.

In this embodiment, Pt is supported on the surface of the carbon nanotube by sputtering. Since sputtering has directivity and does not have a chiral effect, a large amount of Pt is not supported in the carbon nanotube tube as in the prior art. In other words, in the present embodiment, a large amount of Pt can be supported outside the inside of the carbon nanotube, or approximately 100% of the Pt fine particles supported on the carbon nanotube are supported on the outer surface of the tube. be able to. Therefore, when the supported Pt is used as a catalyst, wasteful Pt of the supported Pt is reduced, and the catalyst efficiency can be dramatically increased.

In the present embodiment, the heater 17 is attached to the outside of the vacuum vessel 1, and the hexagonal barrel 1 b can be heated up to 600 ° C. by the heater 17. For this reason, when the inside of the vacuum vessel 1 is evacuated, the hexagonal parel is heated by the heater 17 to vaporize and exhaust the water in the hexagonal barrel. be able to. Therefore, water in the hexagonal barrel

Therefore, aggregation of the carbon support can be prevented more effectively.

In the present embodiment, a piper 18 is attached to the outside of the vacuum vessel 1, and the vibrator 18 can apply vibration to the powder 3 in the hexagonal barrel. This makes it possible to more effectively prevent the carbon carrier from aggregating.

In the present embodiment, since the catalyst fine particles are supported on the surface of the carbon support 3 by the polygonal barrel sputtering method, it is not necessary to treat the waste liquid as in the conventional impregnation method, and the load on the environment can be reduced. There is an advantage.

In this embodiment, catalyst fine particles are supported on a carbon support, but fine particles or thin films other than catalyst fine particles may be supported on a carbon support. In addition, since the carbon-supported catalyst manufactured by the manufacturing method according to the present embodiment supports Pt fine particles, it can be used as an electrode catalyst for fuel cells (anode, force sword) and an industrial catalyst. If a material other than Pt is supported, it can be used for various surface-modified carbon materials other than fuel cell electrode catalysts and industrial catalysts. For example, industrial catalysts (aromatic hydrogenation, selective hydrogenation of unsaturated aldehydes, selective CO oxidation, selective hydrogenation of cation aldehydes, NO decomposition, ammonia synthesis, hydrogenation of citral, hydrogenation of crotonaldehyde, etc.) It can be used for sensors, Li battery materials, photocatalysts, STM and SFM probes, field emitters, rubber and resin fillers, conductive resin fillers, and the like. In the first embodiment, vibration is applied to the carbon carrier 3 in the hexagonal barrel by the vibrator 18, but in the hexagonal barrel instead of the vibrator 18 or in addition to the vibrator 18. It is also possible to apply vibration to the carbon support 3 by rotating the hexagonal barrel while the rod-shaped member is accommodated in the cylinder. Thereby, it becomes possible to prevent aggregation of the carbon support more effectively. Next, electron microscope observation, EDX (energy dispersive X-ray analysis), XRD (X-ray diffraction) of a sample (carbon supported catalyst) in which Pt fine particles are supported on the outer surface of the carbon nanotube by the above-described carbon supported catalyst production method Method) and XRF (fluorescence X-ray analysis) The results will be described.

2 and 3 are photographs obtained by observing, with an electron microscope, a carbon-supported catalyst in which Pt fine particles are supported on the outer surface of the carbon nanotube by the manufacturing method according to the present embodiment.

As shown in Figs. 2 and 3, it was confirmed that Pt fine particles were supported on the outer surface of the carbon nanotube. Specifically, it was confirmed that most of the Pt fine particles were supported on the outer surface of the carbon nanotube, and almost no pt fine particles were supported inside the carbon nanotube tube. Note that the Fe fine particles attached to the carbon nanotubes shown in FIG. 2 are not attached by the polygonal barrel sputtering apparatus according to the present embodiment, but before the Pt fine particles are supported by the polygonal parallel sputtering apparatus. It was attached to the carbon nanotube. This is because in the carbon nanotube manufacturing stage, Fe fine particles were used as seed crystals, and carbon nanotubes from which these seed crystals were not removed were used in this embodiment.

FIG. 4 is a graph showing the particle size distribution of Pt fine particles supported on the carbon supported catalyst shown in FIG. This figure shows the distribution of diameters from the measured results of the diameters of 100 randomly selected Pt particles in the photograph of Fig. 2. As shown in FIG. 4, the average diameter of 100 Pt microparticles is 1.95 nm, and 90% of all particles are between 1.4 and 2.2 nm in size. Existing. Therefore, it was confirmed that Pt fine particles having a uniform particle size were supported.

FIG. 5 (A) is a diagram showing the result of analyzing the carbon nanotube before supporting Pt by ED X (energy dispersive X-ray analysis). FIG. 5 (B) is a diagram showing the result of EDX analysis of a carbon-supported catalyst in which Pt fine particles are supported on the outer surface of a carbon nanotube by the manufacturing method according to the present embodiment.

As shown in FIGS. 5 (A) and 5 (B), it was confirmed that Pt fine particles were supported on the carbon nanotubes by the polygonal barrel sputtering device.

FIG. 6 shows the outer surface of the carbon nanotube by the manufacturing method according to the present embodiment. XRD of carbon supported catalyst with Pt fine particles supported on the surface

It is a figure which shows the result analyzed. As shown in this figure, it was confirmed that Pt fine particles were supported on the carbon nanotubes by a polygonal barrel sputtering apparatus. 67. At the 4 ° P t (220) peak, the particle size of 1; determined by the Sierra equation is 1.85 nm, which is almost equal to the average particle size shown in Fig. 4 obtained from the TEM photograph. Match.

FIG. 7 is a diagram showing a result of analyzing a carbon-supported catalyst in which Pt fine particles are supported on the outer surface of a carbon nanotube by XRF (fluorescence X-ray analysis) by the manufacturing method according to the present embodiment. As shown in this figure, it was confirmed that Pt fine particles were supported on the carbon nanotubes by a polygonal barrel sputtering apparatus.

(Embodiment 2)

A polygonal barrel sputtering method and a carbon-supported catalyst manufacturing method according to Embodiment 2 in which catalyst fine particles are supported on a carbon support 3 using the polygonal parel sputtering apparatus shown in FIG. 1 will be described.

First, about 0.5 gram of carbon support 3 is introduced into the hexagonal barrel 1b. As this carbon support 3, vapor grown carbon fiber (VGCF) manufactured by Showa Denko was used. A nail was used as the dispersing member. In addition, Pt was used for target 2. Then, make a high vacuum in the hexagonal barrel 1 in b with a turbo molecular pump 10 and vacuum the hexagonal barrel to 8 X 10- ⁴ P a. Thereafter, argon gas is introduced into the hexagonal barrel 1 b by the argon gas supply mechanism 16. At this time, the argon gas flow rate is about 20 ccm, and the argon gas pressure is about 0.8 Pa. Then, by rotating the hexagonal barrel 1b for 30 minutes at an angle of 75 ° and 3.5 rpm by the rotation mechanism, the VGCF in the hexagonal barrel 1b and the nail that is a member to be agitated are agitated and rotated. To disperse the agglomerated VGCF. At the same time, a high frequency output of 50 W, for example, is applied between the target 2 and the hexagonal parallel 1 b by the high frequency application mechanism, so that Pt is sputter deposited on the surface of the VGCF at room temperature. At that time, the target is VGC 00 Ran 885

16

Directed in the direction of F. In this way

A child can be carried.

In the second embodiment, the same effect as in the first embodiment can be obtained.

Next, the result of electron microscope observation, XRD (X-ray diffraction method) and XRF (fluorescence X-ray analysis) of the sample (carbon supported catalyst) in which Pt fine particles are supported on the outer surface of VGCF by the above-mentioned method for producing carbon supported catalyst Will be described.

8 and 9 are TEM photographs of a carbon-supported catalyst in which Pt fine particles are supported on the outer surface of VGCF by the manufacturing method according to the present embodiment, which is observed with an electron microscope.

As shown in FIGS. 8 and 9, it was confirmed that Pt fine particles having a relatively uniform particle size were uniformly supported on the outer surface of VGCF.

FIG. 10 is a graph showing the particle size distribution of Pt fine particles supported on the carbon supported catalyst shown in FIG. This figure shows the diameter distribution of 100 randomly selected Pt particles in the photograph in Fig. 8 and shows the diameter distribution. As shown in FIG. 10, the average diameter of 100 Pt microparticles is 2. l nm, and 90% of all particles are present between 1.2 and 3.0 nm in size. Therefore, it was confirmed that Pt fine particles having a uniform particle size were supported.

FIG. 11 is a diagram showing the results of analysis by XRD (X-ray diffraction method) of a carbon-supported catalyst in which Pt fine particles are supported on the outer surface of VGC F by the manufacturing method according to the present embodiment. As shown in this figure, it was confirmed that PGC fine particles were supported on VGC F by a polygonal parel sputtering device. Note that the graphite peak in Fig. 11 is attributed to VGCF, and is also observed in VGCF before supporting Pt. 67. At the Pt (220) peak at 4 °, the particle size of Pt determined by the Sierra equation is 2.3 nm, which is almost equal to the average particle size shown in Fig. 10 obtained from the TEM photograph. Match.

Figure 12 shows the result of XRF (fluorescence X-ray analysis) analysis of a carbon-supported catalyst in which Pt fine particles are supported on the outer surface of VGCF by the manufacturing method according to the present embodiment. It is a figure which shows a fruit. As shown in this figure, VGC

It was confirmed that Pt fine particles were supported by the device.

Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, it is possible to appropriately change the supporting conditions for supporting the catalyst fine particles on the carbon support.

In this embodiment, Pt is used as the material for the catalyst fine particles. However, the present invention is not limited to this, and other fine particles such as metals (A1, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Tl, Pb, etc.) or non-metal (Si, As, C, etc.) It is also possible to use an alloy of each of the metals or nonmetals, or an oxide, nitride, boride, or carbide of each of the metals or nonmetals.

Claims

The scope of the claims

1. a vacuum vessel containing a carbon support, the inner shape of the cross section being substantially parallel to the direction of gravity, and a polygonal shape;

A dispersion member that is placed in the vacuum vessel and disperses secondary particles formed by agglomerating primary particles of the carbon support into primary particles or secondary particles smaller than the original secondary particles;

A sputtering target disposed in the vacuum vessel;

Comprising

The carbon carrier in the vacuum vessel is agitated by performing a rotation operation that rotates the vacuum vessel in one direction using the rotation mechanism, or a pendulum operation that repeats the rotation operation in the opposite direction after rotating in one direction. Alternatively, the polygonal parel sputtering apparatus is characterized in that fine particles or thin films are supported on the surface of the carbon carrier by performing sputtering while dispersing the secondary particles of the carbon carrier by the dispersing member while rotating.

2. The polygonal barrel sputtering apparatus according to claim 1, wherein the dispersion member includes at least one of a powdery substance, a rod-like substance, a small piece, a spherical substance, and a substance having a plurality of protrusions.

3. The polygonal parel sputtering apparatus according to claim 1, further comprising a vibrator for applying vibration to the vacuum vessel.

4. The polygonal barrel sputtering apparatus according to any one of claims 1 to 3, further comprising a heater for heating the carbon carrier in the vacuum vessel.

5.In a vacuum vessel having a polygonal internal shape in a cross section substantially parallel to the direction of gravity, the secondary particles formed by agglomeration of the carbon support and the primary particles of the carbon support are combined with the primary particles or the original particles. Contains a dispersion member to be dispersed into secondary particles smaller than the secondary particles;

By performing a pendulum operation that repeats a rotation operation in which the vacuum vessel is rotated in one direction about a direction substantially perpendicular to the cross-section, or a rotation in the opposite direction after rotating in one direction, the vacuum vessel Sputtering is performed while dispersing the secondary particles of the carbon support by the dispersion member while stirring or rotating the carbon support inside, thereby supporting fine particles or a thin film on the surface of the carbon support. A method for producing a surface-modified carbon material.

6. The carbon support according to claim 5, wherein the carbon support is a single-walled carbon nanotube, a double-walled carbon nanotube, a multi-walled carbon nanotube, a carbon nanohorn, a carbon nanocoil, a cup-stacked carbon nanotube, a bamboo-shaped carbon nanotube, or a vapor-grown carbon fiber. A method for producing a surface-modified carbon material, characterized in that it is at least one of carbon nanofiber, graphite nanofiber, fullerene, carbon plaque and carbon single crystal.

7. Rotating operation of rotating a vacuum vessel having an internal cross-sectional shape of a polygon in one direction about a direction substantially perpendicular to the cross-section, or rotating in one direction after rotating in one direction. Surface modification characterized by carrying out repetitive pendulum action and performing sputtering while stirring or rotating the carbon carrier in the vacuum vessel, whereby fine particles or thin films are supported on the outer surface of the carbon carrier. Carbon material.

8. The surface-modified carbon material according to claim 7, wherein the carbon support is a carbon nanotube, and a larger amount of the fine particles or thin film is supported on the outer surface of the carbon nanotube than in the tube of the carbon nanotube. .

9. The surface-modified carbon material according to claim 8, wherein approximately 100% of the fine particles or thin film supported on the carbon nanotubes are supported on an outer surface of the tube.