KR20140048573A - Amorphous silicon oxide coated carbon-based composite, preparation method thereof and electrocatalyst for fuel cell manufactured by using the same - Google Patents

Abstract

The present invention relates to a preparation method of an amorphous silicon oxide coated carbon-based composite which comprises: a step of coating the surface of a carbon material with a silane polymer by putting the carbon material and the silane polymer into a solvent, and stirring the mixture; a step of evaporating the solvent and drying the carbon-based composite coated with the silane polymer; and a step of heat-processing the carbon-based composite coated with the silane polymer.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a carbon composite material coated with amorphous silicon oxide, an amorphous silicon oxide-coated carbon composite material, a method of manufacturing the same, and an electrode catalyst for a fuel cell using the same. BACKGROUND ART [0002]

The present invention relates to a carbon composite coated with amorphous silicon oxide, a method of manufacturing the same, and an electrode catalyst for a fuel cell using the same. More particularly, the electrochemical corrosion resistance is enhanced, and the highly durable amorphous silicon oxide coated with controlled surface hydrophobicity is coated. The present invention relates to a carbon composite, a method for preparing the same, and an electrode catalyst for a fuel cell using the same.

Electrode catalyst, the core material of fuel cell, mainly uses platinum suitable for hydrogen oxidation and oxygen reduction reaction. Prolonged operation causes catalyst deterioration problems such as elution of platinum and corrosion of the carbon support, and the active area of the catalyst is drastically reduced, shortening the life of the fuel cell. For this reason, it is urgently required to increase the activity of the oxygen reduction catalyst and to enhance the stability and durability for a long time, and it is the greatest issue in commercializing fuel cells.

The supported catalyst is mainly used to increase the stability and active surface area of the catalyst, and a carbon material having a large specific surface area such as carbon black is mainly used as the catalyst carrier. Durability of fuel cell catalysts starts from the improvement of the catalyst carrier, and active research is being conducted in this regard.

Among them, studies using carbon nanofibers and carbon nanotubes as carbon supports have been reported to have superior durability compared to carbon black used mainly. In addition, carbon nanotubes and carbon nanofibers have high electrical conductivity, excellent mechanical properties, and have a high surface potential as a catalyst support because they have a unique surface structure.

Korean Patent Laid-Open Publication No. 2006-0028032 discloses an electrode substrate selected from carbon paper or carbon cloth, an activated carbon layer positioned on the surface of the electrode substrate, and a nanocarbon bonded to the surface of the activated carbon layer and the nanocarbon. A fuel cell electrode comprising a coated catalyst, the surface of the catalyst is large, relates to a fuel cell electrode that can improve the performance of the fuel cell using a small amount of catalyst.

In order to further increase the adhesion of the catalyst particles and the specific surface area of the support, surface treatment is performed on the carbon material. In this case, the activity is improved but the durability tends to deteriorate. A typical method is to generate functional groups containing oxygen on the surface by electrochemical oxidation using strong acid, but this treatment is known to significantly degrade the structure and electrical properties of carbon nanotubes due to the destruction of graphite structure. Due to these problems, research into introducing metal oxides, polymers, and the like into catalyst carriers is being conducted, but since the material is very low in electrical conductivity, there is a technical difficulty in preparing a high activity electrochemical catalyst.

The present inventors have intensively studied to solve the above-mentioned problems, and as a result, silicon oxide, which can compensate for the weakness of the carbon material, which generally has a weak metal-support interaction, and enhance the corrosion resistance of the support, is introduced to the surface of the carbon material. A new material was synthesized by a hybrid method, and a highly durable oxygen reduction catalyst using the same was developed.

Accordingly, an object of the present invention is to provide a carbon composite material coated with a highly durable amorphous silicon oxide coated with enhanced electrochemical corrosion resistance and surface hydrophobicity, a method for producing the same, and an electrode catalyst for a fuel cell using the same.

In order to achieve the above object, the present invention provides a method of manufacturing a carbon nanotube, comprising: coating a carbon material and a silane polymer in a solvent and stirring the silane polymer on the surface of the carbon material; Evaporating the solvent and drying the carbon composite coated with the silane polymer; And it provides a method for producing an amorphous silicon oxide-coated carbon composite comprising the step of heat-treating the amorphous silane polymer-coated carbon composite.

In one embodiment of the present invention, the carbon material may be carbon nanotubes, carbon nanofibers, carbon black, activated carbon, graphite (artificial or natural) and the like, but is not limited thereto.

In one embodiment of the present invention, the silane polymer may be polycarbomethylsilane.

In the present invention, the carbon composite material coated with the silane polymer may be dried, pulverized and heat treated, and the heat treatment may be performed by a first heat treatment and a second heat treatment.

The present invention provides a carbon composite material coated with a high-durability amorphous silicon oxide having enhanced electrochemical corrosion resistance and controlled surface hydrophobicity, and a method for manufacturing the carbon composite material, and using the same as a carrier of an electrode catalyst for a fuel cell, The chemical corrosion resistance can be enhanced and the durability can be improved.

1 is a graph showing the thermal weight measurement results of the plate lit carbon nanofibers used in Example 1 according to the present invention.
FIG. 2 is a graph showing the results of thermogravimetry of the amorphous silicon oxide-coated carbon composite prepared in Examples 1 to 3 according to the present invention.
FIG. 3 is a graph comparing the nitrogen adsorption of PS / PCNF prepared in Example 1 with carbon nanofibers coated with amorphous silicon oxide coated with PCNF at 300 ° C, 400 ° C and 500 ° C, respectively, in Test Example 2 according to the present invention Fig.
FIG. 4 is a graph showing the results of measurement of PS / PCNF prepared in Example 1 in Test Example 3 according to the present invention, in which the amorphous silicon oxide-coated carbon composite prepared by different heat treatment times of 2 hours, 4 hours, The results are shown in FIG.
5 is a graph showing the results of nitrogen adsorption after the first heat treatment at 400 ° C for the samples of Examples 1 to 3 in Test Example 4 according to the present invention.
FIG. 6 shows nitrogen adsorption for the sample of Example 1 prepared after the first heat treatment (400 ° C., 2h, Air) in Example 5 according to the present invention after the second heat treatment at different temperatures in a nitrogen atmosphere. A graph showing one result.
(A) and (b) of FIG. 7 are SEM images of 50000 magnification and SEM images of 100000 magnification, respectively, taken for the platelet-carbon nanofibers used in Example 1, and FIGS. 7 (c) and (d) Are SEM pictures of 50000 magnification and SEM pictures of 100000 magnification, respectively, taken for Sample 5 in Test Example 1 according to the present invention.
(A) and (b) of FIG. 8 are the SEM photograph of 50000 magnification taken about the sample 14 in the test example 1 which concerns on this invention, and the SEM photograph of 50000 magnification taken about the sample 15, respectively.
9 (a) and 9 (b) are TEM photographs taken with respect to the platinum-carbon nanofibers used in Example 1. Fig.
(A) and (b) of FIG. 10 are TEM photographs taken with respect to Sample 14 in Test Example 1 according to the present invention, and FIGS. 10 (c) and (d) show Test Example 1 of the present invention. TEM image taken for sample 5.
(A) and (b) of FIG. 11 are TEM photographs taken with respect to Sample 15 in Test Example 1 according to the present invention, and FIGS. 11C and 11D show samples of Test Example 1 according to the present invention. TEM picture taken for 16.
12 is a CV graph before and after the durability test of 40% Pt / PCNF and 40% Pt / silica-PCNF in Test Example 8 according to the present invention.
13 is an ORR graph before and after the durability test of 40% Pt / PCNF and 40% Pt / silica-PCNF in Test Example 8 according to the present invention.
14 is a schematic view of a carbon composite material coated with amorphous silicon oxide according to the present invention.

Hereinafter, a method for producing the carbon composite material coated with amorphous silicon oxide according to the present invention will be described in detail.

First, the carbon material and the silane polymer are put in a solvent and stirred to coat the silane polymer on the surface of the carbon material.

As the carbon material used in the present invention, carbon nanotubes, carbon nanofibers, carbon black, activated carbon, graphite (artificial or natural) and the like can be used.

 As the carbon material, it is preferable to use platelet-carbon nanofibers in which a graphene layer is arranged perpendicular to the fiber axis.

The silane polymer used in the present invention: the carbon material is preferably used in 1 to 25:99 to 75% by weight.

When the silane polymer is used in less than 1% by weight, the durability improvement effect is insignificant, and when the silane polymer is used in excess of 25% by weight, a material aggregation phenomenon is severely generated and a problem in that the properties of the carbon material hardly appear. Can be.

In one embodiment of the present invention, the carbon nanotubes may be used as the carbon material, and polycarbomethylsilane of the following formula (1) may be used as the silane polymer.

In this case, in order to coat the polycarbomethylsilane of the following Chemical Formula 1 on the surface of the carbon nanotubes, the carbon nanotubes and the polycarbomethylsilane are added to the solvent and stirred:

[Chemical Formula 1]

It is preferable to mix polycarbonmethylsilane and carbon nanotube in the solvent at a weight ratio of 1:99 to 1: 2, respectively.

When the polycarbomethylsilane and the carbon nanotube are used in an amount of less than 1:99 by weight, the effect of coating the polycarbomethylsilane may be insignificant. When the polycarbomethylsilane and the carbon nanotube are mixed at a ratio of 1: 2 When used in excess of the weight ratio, the polycarbonmethylsilane coated on the carbon nanotubes may aggregate on the surface.

In the present invention, a solvent which can be used to dissolve and stir the carbon material and the silane polymer is n-pentane, n-hexane, n-heptane, n-octane, n-decane, dicyclopentane, benzene, toluene, xylene Hydrocarbon solvents selected from the group consisting of durene, indene, tetrahydronaphthalene, decahydronaphthalene and squalane; Dipropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, tetrahydrofuran, tetrahydropyran and p An ether solvent selected from the group consisting of dioxane; Or a polar solvent selected from the group consisting of propylene carbonate, γ-butyrolactone, N-methyl-2-pyrrolidone, dimethyl formamide, acetonitrile and dimethyl sulfoxide; Halogenated hydrocarbon organic solvents selected from the group consisting of carbon tetrachloride, chloroform, 1,2-dichloroethane, dichloro-methane and chlorobenzene can be used.

More specifically, the solvent and the quantum silane polymer in the flask is completely dissolved using a stirrer and the carbon material is added thereto and stirred in a sealed state to uniformly coat the silane polymer on the surface of the carbon material.

Next, the solvent is evaporated and the carbon composite coated with the silane polymer is dried.

After evaporating the solvent using a rotary evaporator until all the solvent in the flask containing the reactant evaporates, the carbon composite coated with the silane polymer remaining in the flask is completely dried in an oven.

Then, the dried silane polymer is prepared by grinding a carbon composite coated.

Finally, the carbon composite coated with the silane polymer is heat treated.

As described above, the carbon composite material coated with the silane polymer may be heat-treated to increase the number of micro-sized pores by burning the carbon, thereby increasing the specific surface area of the finally prepared silicon oxide-coated carbon composite material.

In one embodiment of the present invention, the step of heat-treating the dried silane polymer-coated carbon composite material may be performed by a first heat treatment and a second heat treatment.

The first heat treatment is performed at 300 to 500 ° C for 2 hours in an air atmosphere or at 250 to 400 ° C for 2 hours in an oxygen atmosphere and the second heat treatment is performed at 300 to 800 ° C in an inert gas atmosphere such as helium, Lt; / RTI >

Referring to FIG. 14, the carbon composite material coated with amorphous silicon oxide prepared according to the above-described method is prepared by coating the surface of the carbonaceous material 10 with the amorphous silicon oxide 20. The carbon composite material of the present invention may be produced by coating a carbon fiber with amorphous silicon oxide as in (a) or by coating amorphous silicon oxide with carbon particles as shown in (b).

In one embodiment of the present invention, it is preferred that the surface of the carbon material is coated with a 0.5 to 5 nm layer of silicon oxide. Here, the oxidation number of silicon in the coated silicon oxide layer is 0.5 ~ 2.

The present invention also provides an electrode catalyst for a fuel cell, which is produced by using a carbon composite coated with an amorphous silicon oxide as a support and using platinum or a platinum-ruthenium alloy as an active metal catalyst.

Hereinafter, preferred embodiments and test examples of the present invention will be described in detail. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical meanings and concepts of the present invention.

The embodiments, test examples, and drawings described herein are preferred embodiments of the present invention, and do not represent all of the technical idea of the present invention, and thus, various equivalents and modifications may be substituted for them at the time of the present application. Can be.

Example  One

(1) Preparation of multi-walled carbon nanotubes and polycarbomethylsilane

Silica-carbon nanofiber composites were prepared using platelet-carbon nanofibers (PCNF, Suntel) among various types of carbon nanofibers. In order to coat silica on PCNF, polycarbomethylsilane (Sigma-Adrich Co.) polymer containing silicon was used as a precursor. The average molecular weight of the polymer is 800, and monomers having a molecular weight of 58 form a chain of 14 to 15 chains. Toluene (Toluene, DC chemical Co.) was used as a solvent to dissolve the polymer. The used toluene had a purity of 99.5% and a boiling point of 110.8 ° C.

(2) Method for producing carbon composite material coated with amorphous silicon oxide

Polycarbomethylsilane was coated on the surface of the carbon nanotubes at a content ratio of polycarbomethylsilane and carbon nanotubes of 0.25: 1 (weight ratio). A fixed amount of polycarbomethylsilane was added to a flask containing 200 ml, and the resultant was completely dissolved by stirring for about 30 minutes using a magnetic stirrer. PCNF was added to the flask, and the mixture was stirred at room temperature for 15 hours to uniformly coat polycarbomethylsilane (PS) on the surface of the PCNF. The solvent was then evaporated using a rotary evaporator. The solvent in the flask was operated at 70 ° C. and 100 rpm until all of the solvent in the flask evaporated. The condensed toluene was stored in a container and reused. In order to completely dry the PS / PCNF complex remaining in the flask, it was dried in a dry oven for 24 hours. The dried PS / PCNF was ground finely and stored in a container.

The prepared PS / CNTs were heat treated using only the first heat treatment and the second heat treatment. In the first heat treatment, the PS / PCNF was heat-treated in an air atmosphere using an electro furnace (Seoyoung Tech) to produce silica by combining silicon of polycarbomethylsilane with oxygen in the air. 200 mg of each sample was taken and the experiment was carried out at different temperatures of 300 ° C, 400 ° C and 500 ° C. The flow rate of air was 200 cc / min, and the temperature increase temperature was 5 ° C. per minute, and when the temperature reached the set temperature (300 ° C., 400 ° C., 500 ° C.), heat treatment was performed for 2 hours. At 400 ° C., heat treatment experiments were further performed for 4 hours and 8 hours. After the heat treatment, the sample was weighed and stored separately in a container. Secondary heat treatment was performed in the same manner as the first heat treatment at 400 ℃ to prepare an amorphous silicon oxide coated carbon composite.

Example  2

Carbon composites coated with amorphous silicon oxide were prepared in the same manner as in Example 1, except that the content ratio of polycarbonylmethylsilane to carbon nanotubes was 0.5: 1 (weight ratio).

Example  3

Carbon composite material coated with amorphous silicon oxide was prepared in the same manner as in Example 1, except that the content ratio of polycarbonylmethylsilane to carbon nanotubes was 1: 1 (weight ratio).

Test Example  1: Thermal weight measurement of amorphous silicon oxide-coated carbon composites prepared under nitrogen atmosphere

After the first heat treatment and the second heat treatment were performed at 400 ° C, the inside of the electric furnace was changed to a nitrogen atmosphere and heat treatment was performed at 500 ° C, 600 ° C, 700 ° C, 800 ° C, and 900 ° C for 1 hour to form amorphous silicon oxide Carbon composite material. As in the first heat treatment, the flow rate of nitrogen was 200 cc / min, and the temperature increase temperature was 5 ° C. per minute.

The weight of the playtite-carbon nanofiber, polycarbomethylsilane, playtreat-carbon nanofiber and polycarbomethylsilane used in Examples 1 to 3 and the air atmosphere or the air atmosphere used in Example 1, The results of thermogravimetry of the amorphous silicon oxide-coated carbon composite prepared under the same nitrogen atmosphere are shown in FIGS. 1 and 2, respectively, and the results are shown in Table 1.

[Table 1]

Referring to Table 1, the samples are all reduced in weight after the heat treatment. The specific surface area of PCNF is 48.29m 2 / g, which shows that the specific surface area is very small, but the specific surface area is increased after silica is coated on the surface. Sample 5, which was subjected only to the first heat treatment at 400 ° C., increased more than two times, and sample 10, which was subjected to the second heat treatment at 700 ° C., increased three times. Although the specific surface areas of samples 5, 6, and 7 having different heat treatment times of 2 hours, 4 hours, and 8 hours at the same heat treatment temperature were found, the specific surface area decreased slightly as the time increased. Comparing the specific surface areas of the samples 5, 15, and 16, which are all the same but different in content ratio, it can be seen that the content ratio increases as the content ratio increases. In the case of the second heat-treated sample, the specific surface area increases with increasing temperature up to 700 ° C., but the specific surface area decreases from 800 ° C. or more.

Referring to FIG. 1, the platelet-carbon nanofibers used in Example 1 have no mass change before 600 ° C., but rapidly decrease in mass from 600 ° C. or higher, and the polycarbomethylsilane has a mass near 200 ° C. Little by little, the mass decreased little by little from 500 degreeC or more. Referring to FIG. 2, the carbon composite coated with amorphous silicon oxide prepared by coating polycarbomethylsilane on the surface of PCNF starts burning of carbon at around 600 ° C., and all of the carbon is burned at around 800 ° C. in a content ratio of 0.25: 1. In the case of 20%, 0.5: 1, 33%, and 1: 1 was confirmed that about 47% of the silica remained.

Test Example 2: Nitrogen adsorption characteristics of the amorphous silicon oxide coated carbon composite of Example 1

Nitrogen adsorption of PS / PCNF prepared in Example 1 at 300 ° C, 400 ° C and 500 ° C, respectively, and amorphous silicon oxide coated carbon composite and PCNF were measured. The results are shown in FIG.

Referring to FIG. 3, carbon composite material coated with amorphous silicon oxide shows a nitrogen adsorption graph in which micro-sized pores are developed, unlike PCNF having almost no pores. In addition, it can be seen that as the temperature increases, the pores of the microsize increase and the total adsorption amount also increases.

Test Example 3: Nitrogen adsorption characteristics of the amorphous silicon oxide-coated carbon composite of Example 1 prepared at different heat treatment time

The nitrogen adsorption of the amorphous silicon oxide-coated carbon composite prepared by varying the PS / PCNF prepared in Example 1 at 400 ° C. for 2 hours, 4 hours, and 8 hours was measured and shown in FIG.

Referring to FIG. 4, all three graphs show graph behaviors in which micropores are developed. In the case of heat treatment for 2 hours, the micro pores were most developed and decreased as the heat treatment time increased.

Test Example 4: Nitrogen adsorption characteristics of the carbon composites coated with the amorphous silicon oxides of Examples 1 to 3

Nitrogen adsorption of the samples subjected to the first heat treatment at 400 ° C. was measured in different content ratios of 0.25: 1, 0.5: 1, and 1: 1 as in Examples 1 to 3, respectively.

Referring to FIG. 5, all three graphs show the behavior of the graphs in which the micropores are developed. As the PS content ratio increases, the micropores develop and the total adsorption amount also increases.

Test Example 5: Nitrogen adsorption characteristics of the carbon composites coated with the amorphous silicon oxide of Example 1 subjected to the second heat treatment

After performing the first heat treatment (400 ℃, 2h, Air) in Example 1 and the second heat treatment at different temperatures in a nitrogen atmosphere, respectively, the nitrogen adsorption of the prepared sample is measured and shown in FIG.

Referring to FIG. 6, the second heat-treated sample at 500 ° C. and 600 ° C. showed a graph shape similar to the sample only undergoing the first heat treatment. At higher temperatures, micro-sized pores develop and the total adsorption amount increases. At high heat treatment temperatures of 700 ° C. or higher, mesosize pores begin to develop. Unlike the previous case, however, as the temperature increases at 700 ° C, the pores of the micro and meso sizes decrease. Due to this pore change, both the specific surface area and the total pore volume decrease as the temperature increases.

Test Example  7: Surface Characterization of Carbon Composite Coated with Amorphous Silicon Oxide

Scanning electron microscope (SEM), transmission electron microscope (TEM, Tecnai F20, philips), and surface area analyzer (Belsorp2 mini, BEL JAPAN) were used to analyze the surface area characteristics of the samples prepared in Test Example 1. To FIG. 11.

Referring to (a) and (b) of FIG. 7, the SEM image of the PCNF without any treatment is shorter than that of the carbon nanotubes, and the characteristic characteristics of the PCNF with graphite plates stacked in the axial direction can be seen. . 7 (c) and (d) are SEMs of samples of amorphous silicon oxide-coated carbon composites subjected to primary heat treatment at 400 ° C., which are almost the same as the shape of the PCNF and are slightly shorter in length. Referring to (a) of FIG. 8, only silica remained pure white through heat treatment in an air atmosphere at 700 ° C., but the shape of PCNF remained like other samples. All the carbon was burned, and only silica remained, and the shape having a space inside was confirmed through the image. 8 (b) shows an image of a sample having a content ratio of 0.5: 1 and subjected to a first heat treatment at 400 ° C. FIG.

9 is a TEM photograph of PCNF without any processing. Particularly in FIG. 9 (a), the (002) plane stacked along the axial direction of the PCNF can be confirmed. 10 (a) and (b) is a sample subjected to the first heat treatment at 700 ℃ can be seen that only the hollow hollow remains. In FIG. 9 (a), it is difficult to grasp the morphology because the dispersion is not ensured, but in FIG. 10 (a), it is possible to identify silica which has the shape of PCNF as it is. 10 and 11 are TEM images of samples having different content ratios. As the content increases, the coating thickness is increased little by little, but it can be seen that silica is generally coated on the surface of about 3 to 5 nm thick. However, it was confirmed that the content ratio of 0.5: 1 or more resulted in the accumulation of polycarbomethylsilane.

Test Example  8: Electrochemical Characterization of Electrode Catalyst Using Carbon Composite Coated with Amorphous Silicon Oxide

Platinum reagent (H2PtCl6) was added to the flask, and 150 ml of 2-propanol and 150 ml of water were used as a solvent, followed by flowing nitrogen gas for about 30 minutes. Then CO gas (40 cc / min) was flowed at 35 ° C. for 5 hours. CO gas was turned off and a carbon composite material coated with amorphous silicon oxide prepared in Example 1, which was used as a support, was added and heated at 90 ° C for 12 hours while refluxing. After cooling to 35 ℃, the catalyst was filtered and dried using a desiccator to prepare an electrocatalyst. The electrochemical characteristics and durability of the catalyst were compared by CV and ORR measurement and durability test.

CV graphs before and after the durability test of 40% Pt / PCNF and 40% Pt / silica-PCNF are shown in FIG. 12, and the calculated values of the active area of the catalyst are shown in Table 2 below. The active area of 40% Pt / PCNF was 24.1m ² / g, and the active area of 40% Pt / silica-PCNF was 27.6m ² / g, confirming that the active area of the catalyst supported on silica-PCNF was rather high. After 4100 cycles at 0.6 ~ 1.1 V, the active area of 40% Pt / PCNF decreased to 19.2m ² / g and 40% Pt / silica-PCNF to 18.3m ² / g. An ORR graph is shown in FIG. 13, and a current density and a half wave potential at 0.9 V are shown in Table 3. 40% Pt / silica-PCNF catalyst showed high current density and half wave potential. In particular, in the endurance test results, the half-wave potential decreased by 20 mV from 850 mV to 830 mV, but 40% Pt / PCNF decreased by only 7 mV from 909 mV to 902 mV. . Through this, it was confirmed that the catalyst supported on silica-PCNF was excellent in both the activity and durability of the oxygen reduction reaction.

[Table 2]

[Table 3]

Claims (13)

Coating the silane polymer on the surface of the carbon material by stirring the carbon material and the silane polymer in a solvent;
Evaporating the solvent and drying the carbon composite coated with the silane polymer; And
Heat-treating the carbon composite material coated with the silane polymer
Method of producing an amorphous silicon oxide coated carbon composite comprising a.
The method according to claim 1,
Wherein the carbon material is selected from the group consisting of carbon nanotubes, carbon nanofibers, carbon black, activated carbon, and graphite.
The method according to claim 2,
Wherein the carbon nanofibers are platelet-carbon nanofibers. ≪ RTI ID = 0.0 > 11. < / RTI >
The method according to claim 1,
Wherein the silane polymer is polycarbomethylsilane. ≪ RTI ID = 0.0 > 11. < / RTI >
The method according to claim 1,
The silane polymer: carbon material is a method for producing an amorphous silicon oxide coated carbon composite, characterized in that the mixture is stirred in 1 ~ 25:99 ~ 75% by weight.
The method according to claim 1,
The solvent is the group consisting of n-pentane, n-hexane, n-heptane, n-octane, n-decane, dicyclopentane, benzene, toluene, xylene, durene, indene, tetrahydronaphthalene, decahydronaphthalene and squalane Hydrocarbon-based solvents selected from; Dipropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, tetrahydrofuran, tetrahydropyran and p An ether solvent selected from the group consisting of dioxane; Or a polar solvent selected from the group consisting of propylene carbonate, γ-butyrolactone, N-methyl-2-pyrrolidone, dimethyl formamide, acetonitrile and dimethyl sulfoxide; A method for producing an amorphous silicon oxide-coated carbon composite, characterized in that it is a halogenated hydrocarbon-based organic solvent selected from the group consisting of carbon tetrachloride, chloroform, 1,2-dichloroethane, dichloro-methane and chlorobenzene.
The method according to claim 1,
Method for producing an amorphous silicon oxide-coated carbon composites, characterized in that the silane polymer coated carbon composites are dried and then pulverized.
The method of claim 7,
The heat treatment of the pulverized silane polymer-coated carbon composite is a method of producing an amorphous silicon oxide coated carbon composite, characterized in that the first heat treatment and the second heat treatment.
The method according to claim 8,
The primary heat treatment of the pulverized silane polymer-coated carbon composite material is performed at 300 to 500 ° C. for 2 hours under an air atmosphere or at 250 to 400 ° C. for 2 hours under an oxygen atmosphere, and the secondary heat treatment is performed at 600 in an inert gas atmosphere. Method for producing an amorphous silicon oxide coated carbon composite, characterized in that carried out at ~ 1000 ℃.
A carbon composite coated with amorphous silicon oxide prepared according to any one of claims 1 to 9.
The method of claim 10,
An amorphous silicon oxide-coated carbon composite, characterized in that the silicon oxide layer is coated on the surface of 0.5 ~ 5 nm.
An electrode catalyst for a fuel cell comprising a support of a silicon oxide-coated carbon composite according to claim 10 or 11 and an active metal catalyst supported on the support.
The method of claim 12,
The active metal catalyst is a fuel cell electrode catalyst, characterized in that the platinum or platinum-ruthenium alloy.

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