JP2014172764A - Metal-carrying porous carbonaceous material, and production method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of a metal-carrying porous carbonaceous material composed of a porous carbonaceous material which carries a metal, in particular metal nano-particles, with a uniform size, by using a technique simpler than the conventional one, and to provide the metal-carrying porous carbonaceous material produced by the technique.SOLUTION: A production method of a metal-carrying porous carbonaceous material includes: a first step to form a metal complex-containing porous polymer by making a metal salt, a coordinate monomer, and an aromatic monomer mix together and polymerizing the mixture with heat; and a second step to form the metal-carrying porous carbonaceous material by infusibilizing, baking, and activating the metal complex-containing porous polymer by means of heating at high temperature.

Description

The present invention relates to a metal-supported porous carbon material and a method for producing the same, and uses a metal complex-containing porous polymer rich in an aromatic ring structure as a precursor, so that a porous carbon material having a graphite structure and a metal are used. Complexation is performed more simply.

In recent years, porous carbon materials are used for various purposes, and thus have been the subject of a very wide range of research and development. For example, porous carbon materials can be used in applications related to adsorbents for harmful substances, gas separation, electric double layer capacitors, and hydrogen storage.

In addition, the composite of the porous carbon material and the metal is performed, for example, in order to enhance their use in catalytic action or specific adsorption of organic molecules. As the most widely used known methods, A method in which a porous carbon material is brought into contact with a metal salt solution, and the metal salt adsorbed on the carbon material is converted into metal nanoparticles by a reducing agent (for example, Patent Document 1 and Non-Patent Document 1) or vapor of a metal complex on the carbon material. Examples thereof include a method of immobilizing metal nanoparticles by acting (Patent Document 2).

However, in the method of bringing the porous carbon material into contact with the metal salt solution, an amount of metal salt that is excessive than the amount of metal to be adsorbed must be used, which is problematic in terms of production cost.

On the other hand, the process for producing a porous carbon material is known to be infusibilized to prevent melting by heat using a commercially available or newly designed and manufactured polymer or carbide as a carbon source (Non-patent Document 2). It is manufactured through a series of heating processes, namely, high-temperature firing for carbonization, and higher activation, in particular, activation for imparting micropores (pore diameter: 2 nm or less).

Thus, the conventional main production methods for metal-supporting porous carbon materials are as follows: (1) producing a polymer or carbide as a carbon source, and (2) making the polymer or the carbide infusible / high-temperature calcined / activated. (3) The resulting porous carbon material is brought into contact with a solution of a metal salt, and then a three-stage process of reducing metal ions is required.
A technique for simplifying the manufacturing method and reducing the amount of the metal salt solution to be used is essential for expanding the production of energy devices that are required in large quantities.

JP 2007-55882 A JP 2008-212918 A

ACS Appl. Mater. Interfaces, 4, 3805 (2012). Macromolecules, 42, 1270 (2009).

The first problem to be solved by the present invention is a method for producing a metal-supporting porous carbon material in which a metal, particularly metal nanoparticles are supported in a uniform size in a porous carbon material by a simpler method than before, and The object is to provide a metal-supporting porous carbon material produced by the technique.
The second problem to be solved by the present invention is to provide an electrochemical capacitor (ultra-high capacity capacitor) including the metal-supporting porous carbon material and having excellent electrical conductivity and an electrode catalyst for a fuel cell. It is.

In order to solve the first problem, the present invention includes a first step of forming a metal complex-containing porous polymer by mixing a metal salt, a coordinating monomer, and an aromatic monomer, followed by heat polymerization. And a second step of forming a metal-supporting porous carbon material by infusibilizing, firing and activating by heating the metal complex-containing porous polymer at a high temperature. A manufacturing method is provided.

In the present invention, since a metal-supporting porous carbon material in which fine metal nanoparticles having a size of several nanometers are stably supported in a porous carbon material having a high specific surface area can be produced, a highly active electrochemical capacitor Alternatively, an electrode catalyst for a fuel cell can be provided, and the second problem can be solved.

The metal-supported porous carbon material provided by the production method of the present invention facilitates the size of metals, particularly metal nanoparticles, in the porous carbon material by adjusting the amount of metal salt and coordination monomer to be added. There is an advantage that can be controlled.
Further, the metal-supported porous carbon material of the present invention is a high specific surface area material that contains abundant nm-sized pores ranging from mesopores to micropores, and has a synergistic effect with the supported metal nanoparticles. Since it has very high electrical conductivity and can continuously generate oxidation / reduction reactions by catalytic action of metal nanoparticles, it is useful as an active material for electrochemical capacitors and fuel cells.

It is a conceptual diagram showing the manufacturing process of the metal carrying | support porous carbon material of this invention. It is a schematic diagram of the electric furnace for performing infusibility, baking, and activation among the manufacturing processes of the metal carrying | support porous carbon material of this invention. (A) It is a scanning electron microscope image of the metal complex containing porous polymer [MP-1] manufactured in Example 1. (B) It is a scanning electron microscope image of the metal carrying | support porous carbon material [MC-1] manufactured in Example 1. FIG. (A) It is a transmission electron microscope image of the metal complex containing porous polymer [MP-1] manufactured in Example 1. FIG. (B) It is a transmission electron microscope image of the metal carrying | support porous carbon material [MC-1] manufactured in Example 1. FIG. 1 is a drawing showing a wide-angle X-ray diffraction profile of a metal-supporting porous carbon material [MC-1] manufactured in Example 1. (A) It is drawing showing the cyclic voltammogram (CV) in the 0.5M sulfuric acid of the catalyst electrode [MFC-1] for fuel cells manufactured in Example 2. FIG. (B) It is drawing which represents CV measured in the presence of 2M methanol in the 0.5M sulfuric acid of the catalyst electrode [MFC-1] for fuel cells manufactured in Example 2. FIG.

Hereafter, the principal part for implementing this invention is demonstrated.
The metal-supported porous carbon material of the present invention is prepared by mixing a coordination monomer (L) and a metal salt (S) to prepare a metal complex-containing monomer (Lm), which is used as an aromatic-containing crosslinkable monomer (Am). The polymerizable composition (A) obtained by mixing with the solvent (M) and the solvent (M) and the additive (D) to prepare a composition (X), which is polymerized through a phase separation process The first step of forming the complex-containing porous polymer, followed by stepwise heating the metal complex-containing porous polymer to infusibilize / fire / activate the metal-supporting porous carbon material. It consists of the 2nd process to form.

The coordinating monomer (L) used in the first step is not particularly limited as long as it can coordinate to a metal contained in the metal salt (S) described later to form a metal complex. A monomer having a ring is preferably used. The reason is that by introducing an aromatic ring, it is possible to improve the dispersibility in the aromatic-containing crosslinkable monomer (Am) used in excess, and promote the formation of a graphite structure when firing in the second step. This is because, when used as a catalyst for an electric double layer capacitor or a fuel cell, there is an advantage that the conductivity can be improved. As a coordinating monomer having such an aromatic ring, 4- (diphenylphosphino) styrene, 4-vinylpyridine, 3-vinylpyridine, 2-vinylpyridine, 1-vinylimidazole, 4-vinyl-2,2 ′ -Although bipyridine etc. can be mentioned, it is not restricted to this. Moreover, 1-vinyl-2-pyrrolidinone, acrylonitrile, etc. can be preferably used as a coordinating monomer that does not interfere with the formation of the graphite structure after firing.

Examples of the metal salt (S) used in the first step include salts of transition metals such as Pd, Pt, Ru, Rh, Au, and Ag. For example, iodate, bromate, chlorate, Fluorate, nitrate, perchlorate, phosphate, sulfate, sulfite, acetate, acetylacetonate, oxalate, gluconate, p-toluenesulfonate, and the like can be preferably used. Among these, chlorates, acetates, and nitrates of the metals can be particularly preferably used. These metal salts can be used alone or in combination of two or more.

In the first step, the metal complex-containing monomer (Lm) is prepared by mixing the coordination monomer (L) and the metal salt (S). As an example of the preparation method, the coordination monomer and the metal salt are prepared. The method of stirring in the state melt | dissolved in the solvent can be mentioned. The solvent is not particularly limited as long as it does not dissolve the coordination monomer (L) and the metal salt (S) and prevent the formation of the metal complex. The stirring conditions are not particularly limited as long as the coordination monomer (L) and the metal salt (S) can be completely complexed.

The formed metal complex-containing monomer (Lm) is mixed with an excess amount of the aromatic-containing crosslinkable monomer (Am) to prepare a polymerizable composition (A), which is further mixed with the solvent (M). The composition (X) is polymerized to form a metal complex-containing porous polymer through a phase separation process. Here, the polymer (P _A ) produced by the polymerization of the polymerizable composition (A) becomes incompatible with the solvent (M), and the polymer (P _A ) and the solvent (M) cause phase separation. , a state in which the solvent (M) is incorporated between the polymer _{(P a)} or inside the polymer _{(P a).} By removing this solvent (M), the region occupied by the solvent (M) becomes pores, and a metal complex-containing porous polymer can be formed.

The aromatic-containing crosslinkable monomer (Am) that can be used in the present invention is not particularly limited as long as it can be copolymerized with the metal complex-containing monomer (Lm) to form a copolymer (P _A ). The polymerization is carried out in the presence or absence of a polymerization initiator, and those having a vinyl group are preferred, and among them, a reactive styryl compound is preferred. Examples thereof include 1,3-divinylbenzene, 1,4-divinylbenzene, 1,3-dipropenylbenzene and 1,4-dipropenylbenzene. These aromatic-containing crosslinkable monomers (Am) can be used alone or in admixture of two or more.

Further, for the purpose of adjusting the viscosity, it may be used by mixing with a polymerizable compound having one vinyl group, particularly a styryl compound having one vinyl group. Examples of the styryl compound having one vinyl group include styrene, propenylbenzene, 4-methylstyrene, 4-ethylstyrene, 4-methoxystyrene, 4-chlorostyrene, 1-vinylnaphthalene, and 9-vinylanthracene. .

The solvent (M) is not limited as long as a uniform composition is obtained together with the polymerizable composition ( _A ) and is not compatible with the polymer (P _A ). The solvent (M) may be a single solvent or a mixed solvent. In the case of a mixed solvent, the component alone may not be compatible with the polymerizable composition (A). . Examples of the solvent (M) include alkyl esters of fatty acids such as ethyl acetate, methyl decanoate, methyl laurate, and diisobutyl adipate, and ketones such as acetone, 2-butanone, isobutyl methyl ketone, and diisobutyl ketone. , Diethyl ether, tetrahydrofuran, 1,4-dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and other ethers, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, etc. Aprotic polar solvents, aromatic hydrocarbons such as benzene and toluene, aliphatic hydrocarbons such as hexane and octane, dichloromethane, chloroform, and carbon tetrachloride. Halogenated hydrocarbons, methanol, ethanol, 2-propanol, 1-butanol, 1,1-dimethyl-1-ethanol, hexanol, alcohols such as decanol, and include a solvent such as water. Among these solvents, when used as a single solvent, aprotic polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, methanol, ethanol, Highly polar alcohols such as -propanol and 1,1-dimethyl-1-ethanol are in phase with the polymerizable composition (A) containing the metal complex-containing monomer (Lm) and the aromatic-containing crosslinkable monomer (Am). Since it dissolves easily, it is preferably used. In addition, in order to control the specific surface area of the metal complex-containing porous polymer, a highly polar solvent such as acetone, N, N-dimethylformamide, N, N-dimethylacetamide, methanol, ethanol, 2-propanol, A mixed solvent with a neutral solvent such as compatible tetrahydrofuran, 1,4-dioxane, diethylene glycol dimethyl ether and the like is also preferably used.

Various additives (D) such as a polymerization initiator or a soluble polymer may be added to the composition (X) in order to adjust the polymerization rate, the polymerization degree, and the porous structure of the polymer. .

The polymerization initiator is not particularly limited as long as it can polymerize the polymerizable composition (A), and a radical polymerization initiator, an anionic polymerization initiator, a cationic polymerization initiator, and the like can be used. For example, 2,2′-azobisbutyronitrile, 2,2′-azobiscyclohexanecarbonitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (2-methylbutyrate) Nitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 4,4′-azobis (4-cyano) Valeric acid), dimethyl 2,2′-azobisisobutyrate, 2,2′-azobis (2-methylpropionamidoxime), 2,2′-azobis (2- (2-imidazolin-2-yl) propane), 2, Azo initiators such as 2′-azobis (2,4,4-trimethylpentane), benzoyl peroxide, di-t-butyl peroxide, t-butyl hydroperoxide, cumene Peroxide initiators such as Roperuokishido the like. Moreover, as a polymerization initiator that functions by the action of active energy rays, p-tert-butyltrichloroacetophenone, 2,2′-diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, etc. Ketones such as acetophenones, benzophenone, 4,4'-bisdimethylaminobenzophenone, 2-chlorothioxanthone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin Benzoin ethers such as isobutyl ether, benzyl ketals such as benzyldimethyl ketal and hydroxycyclohexyl phenyl ketone, and N-azidosulfonylphenylmaleimide. Include the azide. A polymerizable ultraviolet polymerization initiator such as a maleimide compound can also be used. Further, disulfide initiators such as tetraethylthiilam disulfide, nitroxide initiators such as 2,2,6,6-tetramethylpiperidine-1-oxyl, 4,4′-di-t-butyl-2,2′- Living radical polymerization initiators such as bipyridine copper complex-methyl trichloroacetate complex and benzyldiethyldithiocarbamate can also be used.

The soluble polymer can be used without limitation as long as it gives a uniform composition as the composition (X) and is soluble in the solvent (M) alone. By being soluble in the solvent (M), it can be easily removed from the metal complex-containing porous polymer by the removal operation of the solvent (M) after the polymerization of the polymerizable composition (A). Soluble polymers are involved in the phase separation process accompanying polymerization, and have a significant effect on the microstructure of the resulting metal complex-containing porous polymer, especially its specific surface area, pore diameter, pore volume, and polymer fiber diameter. There are many things. As the soluble polymer to be used, it is desirable to use a polymer having a high affinity with an aromatic ring structure such as polystyrene or poly α-methylstyrene, but there is no particular limitation on the type and molecular weight as long as it induces a porous structure. Absent.

The polymerization reaction may be a known method such as a thermal polymerization method and an active energy ray polymerization method performed by irradiation with ultraviolet rays or electron beams. For example, the metal complex-containing porous polymer can be produced by reacting with the above-described thermal polymerization initiator at 40 to 100 ° C., preferably 60 to 80 ° C. for 10 minutes to 72 hours, preferably 6 to 24 hours. it can. In addition, a metal complex-containing porous polymer is produced by reacting at a power of 250 to 3000 W at room temperature for 1 second to 2 hours, preferably 10 seconds to 30 minutes using various mercury lamps and metal halide lamps. Can do.

The method for removing the solvent (M) after polymerizing the composition (X) is not particularly limited, but when the solvent (M) is a highly volatile solvent, it is dried by drying at normal pressure or reduced pressure. be able to. When the solvent (M) is a low volatility solvent, the polymer obtained by polymerizing the composition (X) is brought into contact with a high volatility solvent, the solvent is exchanged, and then dried at normal pressure or reduced pressure. Can be performed. Further, when removing the solvent (M), a solvent in which the compound is dissolved is used for the purpose of removing unpolymerized components among the polymerizable compounds contained in the polymerizable composition (A). It is also effective to perform washing and extraction. The extraction operation can also be performed using a Soxhlet extractor.

About the metal complex containing porous polymer obtained, the hole diameter and intensity | strength of a metal complex containing porous polymer change with content of polymeric composition (A) contained in composition (X). As the content of the polymerizable composition (A) increases, the strength of the porous body improves, but the pore diameter tends to decrease. The preferable content of the polymerizable composition (A) is in the range of 15 to 50% by mass, more preferably in the range of 25 to 40% by mass. When the content of the polymerizable composition (A) is 15% by mass or less, the strength of the porous body is lowered, and when the content of the polymerizable composition (A) is 50% by mass or more, the pore size of the porous body. It becomes difficult to adjust.

Further, in the firing process of the metal complex-containing porous polymer in the second step described later, in the case of a metal complex-containing porous polymer consisting of a thin fibrous polymer having a diameter of 100 nm or less, it easily burns, It becomes difficult to adjust the firing conditions. In order to make the setting of firing conditions easier, it is desirable that the polymer fiber forming the metal complex-containing porous polymer has a relatively thick shape on the order of μm.

The metal content in the metal complex-containing porous polymer produced in the first step of the present invention is preferably about 3% by weight. If the metal content is much less than 3% by weight, the metal nanoparticles in the metal-supported porous carbon material obtained in the second step cannot exhibit sufficient electrochemical characteristics and catalytic activity. When it greatly exceeds%, it becomes easy to precipitate as a bulk metal in the metal-supporting porous carbon material obtained in the second step.

The second step of the present invention is a step of producing a metal-supporting porous carbon material by infusibilizing / firing / activating the metal complex-containing porous polymer formed through the first step using an electric furnace. . At this time, it is desirable to use a cylindrical quartz tube as the furnace core tube, but the present invention is not limited to this. The electric furnace is provided with both a thermocouple for measuring the temperature on the apparatus side and a thermocouple for measuring the temperature inside the furnace core tube, and a thermocouple for measuring the temperature inside the furnace core tube. Connect to the control terminal of the electric furnace.

The second step of the present invention mainly includes three processes of infusibilization / firing / activation. Infusibilization is performed at a low temperature of 190 to 230 ° C. in an air stream to prevent fusion of the sample surface in the subsequent high temperature treatment (700 ° C. or higher). The air flow velocity at this time is preferably 0.1 to 1.0 mL · min ^−1, but is not limited thereto. Moreover, although it is desirable to perform the heat processing for infusibilization for 6 to 24 hours, it is not restricted to this. After infusibilization, the sample is fired by switching the air flow to a nitrogen flow while keeping the sample inside the furnace core tube. The flow rate of the nitrogen stream is preferably 1.0 to 5.0 mL · min ^−1, but is not limited thereto. The heating temperature in the firing is desirably 850 to 1000 ° C., because the subsequent activation reaction does not proceed unless the temperature is 850 ° C. or more (Yuzo Sanada, Motoyuki Suzuki, Satoshi Fujimoto, “New Edition Activated Carbon Fundamentals and Applications”, pp. 11-28). 48-49, Kodansha Scientific, 1992). The heating time is preferably 30 minutes to 2 hours, but is not limited thereto. After firing, activation is performed by mixing carbon dioxide in a nitrogen stream and continuing heating at the same temperature as firing. The flow rate of the carbon dioxide to be mixed is preferably 0.1 to 0.5 mL · min ^−1, but is not limited thereto. The heating time is preferably 30 minutes to 2 hours, but is not limited thereto.

Through the activation treatment as described above, formation of a fine porous structure on the sample surface proceeds. At this time, carbon reacts irreversibly with carbon dioxide gas to become carbon monoxide gas and desorbs from the sample surface. The reaction mechanism is as shown in the following reaction formulas 1 and 2.

By the second step of the present invention, not only a carbon material having a porous structure is obtained, but also metal complexes contained in the sample are diffused and fused in the support by heating to form minute metal nanoparticles.

By passing through each process as described above, a composite in which metal nanoparticles are supported in a porous carbon material can be produced (FIG. 1).
In the method for producing a metal-supporting porous carbon material according to the present invention, the metal complex supported in the metal complex-containing porous polymer is diffused and fused inside the support by firing to form uniform nanoparticles of 5 to 20 nm. To do. Thereby, the manufacturing method of the metal carrying | support porous carbon material by this invention can manufacture a metal carrying | support porous carbon material with high catalytic activity simply. In addition, the size of the metal nanoparticles has an advantage that it can be easily controlled by the amount of the metal complex added in advance.

In the present invention, there are provided an electrode catalyst and an electrochemical capacitor serving as a negative electrode for a fuel cell containing the metal-supported porous carbon material as an electrode active material.
A fuel cell is a type of battery that uses an active material that can be replenished from outside and extracts electricity from an electrochemical reaction. A fuel cell can generate electricity continuously by reacting a negative electrode active material with oxygen (positive electrode active material). Platinum is used as a catalyst for obtaining a negative electrode active material. A porous carbon having a large specific surface area is widely used as a base material for fixing the catalyst.

The electrochemical capacitor is a general term for capacitors that perform charging / discharging using an electric double layer, or in addition, charging / discharging using an electrochemical reaction by an active material. A capacitor that charges and discharges using an electric double layer is called an electric double layer capacitor, and a capacitor that simultaneously uses an active material is called a redox capacitor. Many electrode materials for electrochemical capacitors utilize porous carbon having a large specific surface area for the purpose of increasing the electric double layer capacity.

The metal-supported porous carbon material contained in the catalyst electrode of the present invention as an electrode active material can provide a smooth electron transfer path with high electrical conductivity, and has a micropore and a mesopore by activation treatment. The carbonaceous support has a very large specific surface area, and as a result, the capacitor capacity and output characteristics can be improved. In addition, since the metal-supported porous carbon material of the present invention contains very minute and highly active metal nanoparticles, the metal nanoparticles cause an electrolyte-specific adsorption or Faraday reaction, and as a result, further, the electrochemical capacitor. The capacity has the advantage of enabling catalytic reaction on the electrode surface and improving electrical conductivity. As described above, the electrode catalyst for the fuel cell containing the metal-supported porous carbon material of the present invention as an electrode active material, and other configurations and structures are not particularly limited, and there are no limitations on general materials and structures for the time being. Applicable to.

EXAMPLES Hereinafter, although this invention is demonstrated in more detail using an Example, this invention is not limited to the range of a following example.

Example 1
[Production of metal-supported porous carbon material]
Chloroplatinic acid hydrate (Aldrich) 0.20 g (490 μmol), N, N-dimethylformamide (hereinafter referred to as “DMF”) 1.5 mL and diphenylphosphinostyrene (Aldrich) 0.59 gmg (2.0 mmol) And then shaken at room temperature for 30 minutes, 1.6 mL of DMF in which 0.13 g of polystyrene (Aldrich, M _w = 280,000) was dissolved, 1.3 g of divinylbenzene (Aldrich), azobisisobutyro The mixture was mixed with 0.040 g of nitrile (Wako Pure Chemical Industries, Ltd.) in a cylindrical tube. After nitrogen gas was blown into the mixed solution for 30 minutes, the cylindrical tube was sealed and the polymerization reaction was carried out by heating at 70 ° C. for 10 hours.

Subsequently, the obtained polymer was put into a cylindrical filter paper, washed with tetrahydrofuran using a Soxhlet extractor for 4 hours, washed with methanol for 2 hours, and then dried at 50 ° C. for 15 hours to obtain a metal complex-containing porous polymer. A triphenylphosphine platinum complex-porous polydivinylbenzene complex [MP-1] was prepared.
The produced [MP-1] was placed on a heat-resistant dish, placed in a constant temperature dryer, and heated at 200 ° C. for 15 hours. Take out the triphenylphosphine platinum complex-porous polydivinylbenzene complex, which has changed from white to brown, and cool it naturally to room temperature. Inside the cylindrical quartz furnace core tube installed in the electric furnace as shown in Fig. 2 Put it in. While raising the temperature at 5 ° C. min−1, nitrogen gas (1.0 L · min ⁻¹ ) and nitrogen / carbonic acid mixed gas (1, respectively) at each stage of firing (1 h) and activation (1 h) at 900 ° C. 0 and 0.1 L · min ⁻¹ ) and the composition of the flowing gas were changed to produce a platinum nanoparticle-porous carbon composite [MC-1] which is a metal-supporting porous carbon material.

[Results of analysis of metal-supported porous carbon material]
[MP-1] and [MC-1] were analyzed using a scanning electron microscope, a transmission electron microscope, and wide-angle X-ray diffraction. Table 1, FIG. 3, FIG. 4, and FIG. This is shown in FIG.
The results shown in Table 1 show the specific surface area calculated by the BET method, the average pore diameter obtained by analysis by the BJH method, and the fine pores from the isothermal adsorption lines representing the adsorption / desorption behavior of nitrogen gas on the sample surface. Represents the pore area.
Referring to Table 1, the metal-supporting porous carbon material [MC-1] increases to about 2.8 times the specific surface area of the original metal complex-containing porous polymer [MP-1] by firing, It was confirmed that the pore area increased while the pore diameter was preserved, that is, new pores were formed on the sample surface by firing.

3 (a) and 3 (b) are drawings showing polymer microstructures observed by a scanning electron microscope of [MP-1] and [MC-1], respectively. Referring to FIGS. 3 (a) and 3 (b), while [MP-1] and [MC-1] were confirmed to form a network of polymer spherical masses, [MC-1 ], It was confirmed that the spherical lump surface was finer than the [MP-1] surface.
FIGS. 4A and 4B are detailed microstructures observed by a transmission electron microscope of Pt nanoparticles contained in [MP-1] and [MC-1], respectively. Referring to FIGS. 4 (a) and 4 (b), only [MP-1] was confirmed to be a polymer as a support, while [MC-1] was confirmed to have a large number of 5 to 20 nm Pt nanoparticles. Many of the Pt nanoparticles were confirmed to be single crystals.

FIG. 5 is a drawing showing a wide-angle X-ray diffraction profile in [MC-1]. Referring to FIG. 5, in [MC-1], clear peaks of (111) plane and (200) plane of platinum are confirmed, and peaks indicating that the porous carbon of the support has a graphite-like structure are also shown. Some were confirmed.

(Example 2)
[Manufacture of catalyst electrode for fuel cell using [MC-1]]
10 mg of the manufactured [MC-1] is ground in a mortar for 30 minutes, mixed with 2 mL of Nafion® (5 wt% isopropanol solution) according to the literature (Energy Fuels, 24, 3727 (2010)), dispersed by ultrasonic irradiation, glassy 10 μL of the solution was dropped onto the surface of the carbon electrode (GCE) and dried at 80 ° C. for 30 minutes to produce a fuel cell catalyst electrode [MFC-1] using [MC-1].
The results of analyzing [MFC-1] using cyclic voltammetry are shown in FIG. FIG. 6A shows the result of subtracting the background porous carbon CV from the cyclic voltammogram (CV) of [MFC-1] in 0.5 M sulfuric acid aqueous solution. is there. FIG. 6 (b) shows the CV of [MFC-1] in the presence of 2M methanol.
Referring to FIG. 6A, hydrogen adsorption / desorption and redox peaks characteristic of Pt were confirmed. In addition, referring to FIG. 6B, a strong electromotive force based on methanol oxidation was observed.

(Example 3)
[Production of electrochemical capacitor using [MC-1]]
According to a conventional method (see, for example, Chem. Mater., 23, 5208 (2011)), the produced [MC-1] is mixed with polyvinylidene fluoride (PVDF) and acetylene black in a weight ratio of 85/5 / The slurry obtained by mixing at 10 and grinding and dropping a small amount of N-methylpyrrolidone was applied and spread on an aluminum oxide plate and dried at 80 ° C. The electrode obtained was covered with a porous polypropylene film, and Teflon ( An electrochemical capacitor [MDLC-1] was manufactured by immersing a sandwiched sheet between a (registered trademark) plate in a 0.5 M sulfuric acid aqueous solution.
Table 2 shows the capacitor capacity obtained based on the CV and charge / discharge measurement results for [MDLC-1].

Referring to Table 2, a capacitor capacity calculated from a CV measured at a sweep rate of 100 mV · s ⁻¹ and a capacitor capacity calculated from a charge / discharge measurement performed under a constant current of 5 A · g ^−1. All showed large values. This is about twice the electric double layer capacitor capacity of only porous carbon containing no Pt.

INDUSTRIAL APPLICABILITY The present invention can be applied as a metal-supported porous carbon material to a field related to an electrode catalyst for a fuel cell and an electrochemical capacitor using the same.

Claims (10)

A composite of metal nanoparticles and porous carbon,
A metal-supporting porous carbon material produced by directly firing a metal complex-containing porous polymer as a precursor. The metal-supporting porous carbon material according to claim 1, wherein the metal complex-containing porous polymer is a porous polymer containing a metal complex immobilized on a polymer chain by a covalent bond. The metal complex-containing porous polymer is
(I) a step of preparing a metal complex-containing monomer (Lm) by mixing a coordination monomer (L) and a metal salt (S),
(Ii) The metal complex-containing monomer (Lm) and the aromatic-containing crosslinkable monomer (Am) are mixed to obtain a polymerizable composition (A), and then compatible with the polymerizable composition (A). , the polymerizable composition of the polymer (P _a) and immiscible solvent (M) and additives (D) and mixed to composition (a) (X) was prepared, after polymerization of the composition (X) By removing the solvent (M) and the additive (D) from the polymer (P _A ),
The metal-supporting porous carbon material according to claim 1, which is a formed metal complex-containing porous polymer. The metal-supporting porous carbon material according to claim 3, wherein the metal salt (S) is a salt of one or more metals selected from the group consisting of Pd, Pt, Ru, Rh, Au, and Ag. The metal-supporting porous carbon material according to claim 3 or 4, wherein the coordination monomer (L) has a phosphino group in a molecular structure. The said additive (D) is a polystyrene, The metal carrying | support porous carbon material as described in any one of Claims 3-5. The metal-supporting porous carbon material according to any one of claims 1 to 6, wherein the firing process of the metal complex-containing porous polymer is infusible, fired and activated by stepwise heating. . The metal-supporting porous carbon material according to any one of claims 1 to 7, comprising micropores as a porous structure and having a BET specific surface area of 800 m ² · g ^-1 or more. The electrode catalyst of the electrochemical capacitor which contains the metal carrying | support porous carbon material in any one of Claims 1-8 as an active material. The electrode catalyst of the fuel cell which contains the metal carrying | support porous carbon material in any one of Claims 1-8 as an active material.

Images