KR20070087697A - Porous filamentous nanocarbon and manufacturing method thereof - Google Patents

Abstract

Provided are a porous filamentous nano-carbon having micropores of 2 to 30 nm and a method for producing the same to be used as absorbents, chromatography materials, catalyst supports. The porous filamentous nano-carbon has micropores of a tunnel shape toward a fiber axis from the outer circumferential surface. The porous filamentous nano-carbon has a platelet structure with carbon hexagonal net planes piled vertically to the fiber axis, in which the micropores are formed along the alignment of the carbon hexagonal planes. Also, the porous filamentous nano-carbon has a herringbone structure with the carbon hexagonal net planes aligned in a V shape around the fiber axis with an angle of 20 to 80 degrees, in which the micropores are formed along the alignment of the carbon hexagonal planes. The nano-carbon fiber has a diameter of 2 to 500 nm and an aspect ratio of 4 or more.

Description

POROUS FILAMENTOUS NANOCARBON AND MANUFACTURING METHOD THEREOF

1A is a TEM image of the fibrous nanocarbon of the tube structure.

1B is a TEM image of fibrous nanocarbon with platelet structure

1C is a TEM image of the fibrous nanocarbon of herringbone structure

Figure 2 is a fibrous nanocarbon of the tube structure

3 is a fibrous nanocarbon of platelet structure

4 is a fibrous nanocarbon of a herringbone structure

5 to 8 are TEM images of fibrous nanocarbons in which pores are produced by nano-drilling according to the present invention.

9 is a graph showing the electrochemical activity of the fibrous nano-carbon applied to the present invention

The present invention relates to a porous fibrous nanocarbon having pores formed on the outer circumferential surface, and more particularly, to a porous fibrous nanocarbon formed along the arrangement direction of the small hexagonal netting layer having radial pores from the outer circumferential surface of the nanofiber to the fiber axis direction. It relates to a manufacturing method.

Research into a material having a porous porosity has been actively conducted, and many methods for producing the same are well known. In particular, a method for producing activated carbon and activated carbon fibers, and a method for producing fibrous nanocarbon and carbon nanotubes (hollow ultrafine carbon fibers having a fiber diameter of 80 nm or less) using a metal catalyst Related information is known in many patents and articles. According to this general activation method, a large amount of micropores are formed on the surface of the carbon material to make a porous carbon material commonly called activated carbon.

Activated charcoal and activated carbon fiber are prepared by heat-treating the carbon-based material at a temperature of 300 to 1100 ° C. for a predetermined time in an atmosphere of steam, air, carbon dioxide, and alkali metals such as potassium hydroxide and sodium hydroxide. It is known to prepare the carbon-based material by heat treatment at a temperature of 300 to 1100 ° C. for a predetermined time, and then separately wash and dry the salt.

International Patent Publication No. WO8603455, filed by Hyperion Catalytic International Inc. in 1986, has a fiber diameter of 3.5 to 70 nm, and a carbon hexagonal plane is arranged concentrically on the fiber axis. A technology for hollow nanotube carbon nanotubes has been published. Carbon nanotubes are classified into single wall carbon nanotubes (SWNTs) in which a carbon hexagonal network is composed of a single layer, and multi-walled carbon nanotubes (MWNTs) in multiple layers. It is known that the tube has a fiber diameter of 0.4 to 3.5 nm and the multilayer nanotube has a fiber diameter of about 2.5 to 50 nm.

Fibrous nanocarbon is known in many ways by pyrolysing carbon monoxide and hydrocarbon gas, which are carbon sources, on a metal catalyst. For example, US Pat. No. 4,565,683 describes a method for producing fibrous carbon having a length of 1 μm or more by pyrolysing carbon monoxide and hydrocarbons at a temperature of 540 to 800 ° C. using a catalyst such as iron oxide or iron or nickel. Is disclosed. In addition, Baker and Rodriguez have disclosed a method for producing carbon nanofibers having a surface area of 50 to 800 m 2 / g by pyrolyzing hydrocarbons at a temperature of 500 to 700 ° C. using a catalyst such as iron, nickel, and cobalt. Bomm, Carbon, 11, 583 (Boehm, Carbon, 11, 583) have also announced techniques for producing fibrous nanocarbons by pyrolyzing hydrocarbons using transition metals of iron, cobalt, nickel, or alloys of iron, cobalt, and nickel or their alloys. 1973); H. Murayama, T. Maeda, Nature, 245, 791; Rodriguez, NM. 1993. J. Mater. Res. 8 (3233)).

Carbon nano fiber has a platelet structure in which carbon hexagonal net surfaces are arranged at right angles to the fiber axis, and a herringbone structure having a constant inclination of 20 to 80 ° with respect to the fiber axis. Rodriguez, NM, 1993. J. Mater. Res. 8 (3233)), and unlike nanotubes, does not have a hollow inside the fiber. 1A, 1B, and 1C show TEM images of carbon nanotubes, platelet fibrous nanocarbons, and herringbone fibrous nanocarbons, respectively.

These activated carbons, carbon nanotubes and fibrous nanocarbons are all very large in surface area, and thus can be applied as a support for adsorbents or catalysts. Since the pores are very fine and have a micropore range of 2 nm or less, they are effective for adsorbing small molecules such as gases harmful to the environment and halogenated hydrocarbons that contaminate water. Therefore, although it can be used to remove contaminants by exhaust gas from plants, purify drinking water, etc., it is difficult to use as a catalyst support for converting polymer materials such as polymer adsorbent and crude oil. This is because an absorbent having a mesopore size of 2 to 100 nm and a high uniformity in pore size should be able to be produced at low cost.

Several techniques are known for producing mesopores with medium size.

First, a raw material including a reactant (moiety) that can be removed to a desired size is mixed with a solid and polymerized, and then the above reactant is removed to form a porous solid having pores. For example, the organic material is removed when the polymer mixed with the organic material and the inorganic material is removed, and the remaining inorganic material produces pores that are about the size of the organic material. The porous solids thus made have the advantage of even distribution of mesopores having a medium size, but the manufacturing cost is expensive and the process takes too long.

Recently, the results of synthesizing materials having mesopore of medium size by silica and silica alumina have been published. What is called MCM-41, M41-S is disclosed in US Pat. Nos. 5,108,725, 5,378,440. However, it is an electrically nonconductive and very unstable in alkaline solution and therefore is not suitable for applications such as fuel cells, batteries, electrolysis cells, capacitors and the like.

The following relates to the synthesis of carbon materials with optionally medium mesopores. A method of injecting a carbon source into a template of zeolite, alumina, silica, etc., which has a medium pore, induces carbonization or chemical vapor deposition of pyrolytic carbon from a hydrocarbon gas, and then removes the template with hydrofluoric acid. However, this method is also expensive manufacturing costs, and has many problems in productivity, such as manufacturing period and output.

On the other hand, since the solids of the medium-sized pores made according to the prior art as described above are mostly particulates, despite the advantages of having a high specific surface area, there are problems in handling such as filtering.

Accordingly, the present invention has been made to solve the problems of the prior art as described above, the object is to include a fibrous nanocarbon having a high porosity, uniform size and pores of 2-30nm size (mesopore size) It is to provide a porous fibrous nano-carbon and a method of manufacturing the same.

Another object of the present invention is to provide an absorbent or chromatographic material for separation of polymers such as proteins, electrode materials of fuel cells, porous fibrous nanocarbons for electrochemical reactions, and a method of manufacturing the same.

It is still another object of the present invention to provide a porous fibrous nanocarbon and a method of manufacturing the same, in order to eliminate handling inconveniences by allowing a solid having a medium size of pores to have a fibrous shape of a nano size diameter rather than a particulate.

Porous fibrous nanocarbon according to an embodiment of the present invention for achieving the above object is characterized in that the pores are formed on the outer peripheral surface of the fiber, the pores are characterized in that the tunnel shape formed toward the fiber axis from the outer peripheral surface.

These fibrous nanocarbons are platelet-shaped nanofibers in which the carbon hexagonal mesh layer is vertically laminated with respect to the fiber axis, or the herringbone structure of the carbon hexagonal mesh layer having a V-shaped angle of 20 to 80 ° with respect to the fiber axis. The pores are formed along the arrangement direction of the carbon hexagonal net face layer.

Further, the diameter of the nanofibers is preferably 2 to 500 nm, preferably 10 to 200 nm, an aspect ratio of 4 or more, preferably 10 or more, and a pore size of 2 to 100 nm, preferably 2 to 30 nm, preferably at least 20% or more. Has a porosity of at least 50%.

According to another embodiment of the present invention, a method for preparing porous fibrous nanocarbon includes attaching a material containing a metal catalyst to the outer circumferential surface of the fibrous nanocarbon, and gasifying the carbon hexagonal mesh layer around the metal hexagon in an oxidizing or reducing atmosphere. By removing by gasification, fibrous nanocarbon having pores is produced by activation by a catalyst which forms tunnel-like pores from the outer circumferential surface toward the fiber axis, so-called nano-drilling method.

Tunnel-shaped pores are generated as the metal catalyst selectively reacts with a specific portion of the fibrous nanocarbon to which the metal catalyst is attached. As a result, the carbon hexagonal netting layer on the specific portion where the metal catalyst is attached is removed, and the pores are formed along the arrangement direction of the carbon hexagonal netting layer. Because of this selective reaction, it is possible to control the size of the tunnel pores and the porosity of the fiber, depending on the size of the metal catalyst attached to the fibrous nanocarbon or the conditions of the nano drilling.

Accordingly, nano-sized pores are formed on the outer circumferential surface of the fibrous nanocarbon, and the size of the pores, that is, the diameter of the mesopore of 2 to 30 nm, is used as an electrode material for separation or absorption of polymer compounds such as proteins and crude oil and fuel cells. Application is possible.

FIG. 1 shows a photograph of a fibrous nanocarbon having three typical structures of tubular, platelet, and herringbone type with a high-resolution transmission electron microscope (TEM) and a conventional two-dimensional model.

2 to 4 show that the three types of fibrous nanocarbons described above are formed by dense stacking of structural units called nano-rods. That is, the tunnel-shaped pores according to the present invention are made based on the novel structure of fibrous nanocarbons composed of a stack of carbon nano-rods.

The nano-branch is a basic unit that constitutes fibrous nanocarbon, in which fullene tubes forming a cylinder by overlapping layers of carbon hexagon are overlapped coaxially and their ends are closed (see FIG. 3A). The nano-branch consists of hexagonal pillars having 4 to 6 coaxial axes, having a diameter of about 2.5 nm and a length of 20 to 80 nm. For a description of nano-branches, see S.-H. Yoon, S. Lim, S.-h. Hong, I. Mochida, B. An, K. Yokogawa. 2004, Carbon , 42 (15) , 3087-3095; B. An, K. Yokogawa, S. Lim, S.-H. Yoon, I. Mochida.In: Carbon 2004 International Conference , Brown University: RI (USA), 2004). .

The present invention uses nano-drill processes to form nano-sized pores on the outer surface of fibrous nanocarbons. When the nanocatalyst is attached to the outer surface of the fibrous nanocarbon and heat treated in a hydrogen or oxygen atmosphere to activate the hydrogenation or oxidization gasification reaction, a tunnel of catalyst size is created from the outer surface to the inside. In this way, the pattern in which the tunnel is drilled is not random unlike in the prior art, and is uniformly generated along the arrangement direction of the carbon hexagon network layer. Accordingly, the nanocatalyst in the hydrogenation or oxidizing atmosphere removes the fibrous nanocarbon along the nano-branched layered structure from the portion to which the nanocatalyst is attached, and forms a nano tunnel by drilling a hole.

This reaction is due to the gasification reaction of hydrogen or oxygen with respect to carbon of the metal. The tunnel-shaped cross section forming the sidewalls of the carbon hexagonal network has a higher reactivity of gasification than the base surface, so that the decomposition of the carbon surface by gasification is in the orientation of nano-branched units formed by hexagonal columns of the carbon hexagonal network. Because it happens. Accordingly, the nano-drilling reaction to create the tunnel proceeds from the outer peripheral surface of the fibrous nanocarbon to the fibrous center along the long axis of the nano-branch. This is possible by preferentially gasifying and removing the nano-branches with the catalyst attached to the ends of the nano-branches in a hydrogen or oxygen atmosphere. At this time, since one or more nano-branches may react with the reaction gas by means of a catalyst, a nano tunnel having a width of 2 to 30 nm larger than the diameter of the nano-branches is made. Thus, in the fibrous nanocarbon of herringbone and platelet structures, tunnel pores are formed radially from the outer peripheral surface toward the center of the fiber along the axis in which the nano-branches are oriented.

Metallic catalysts for gasification by catalyst, ie nano drilling, are possible elements of groups V, VI, VII and VIII on the periodic table. Preferred are Fe, Co, Ni, Mo, V, Cr, Pt, Pd, Ru, Cu, Ag, Zn, Sn and alloys thereof. As the alloy catalyst, Ni-Cu, Fe-Ni, Fe-Pt, Fe-Mo, Ni-Mo, Co-Mo, Pt-Ru and the like are preferable. The size of the catalyst is suitable from 2 to 50 nm, and if it is too small, too small micropore will be produced, and if too large, a large part of the fibrous nanocarbon may be consumed.

As the reaction gas for activation, hydrogen and oxygen are preferable, and CO ₂ , SO ₂ , NO, NO ₂ and H ₂ O may also be used. If the reaction conditions are not properly controlled during the activation process, the nano-branched graphite layer may melt or intercalate, so the process temperature should be appropriately adjusted. For example, in the case of hydrogenation, 400-1200 degreeC is preferable, More preferably, it is 500-900 degreeC. Moreover, in the case of oxidation, 100-500 degreeC is preferable, More preferably, it is 200-400 degreeC.

Aspects of the present invention described above will become more apparent through preferred embodiments described with reference to the accompanying drawings. Hereinafter, the present invention will be described in detail so that those skilled in the art can easily understand and reproduce the present invention.

First, a brief description will be given of a method for producing fibrous nanocarbon used in the present invention.

First, the fibrous nanocarbon of the tube structure, that is, carbon nanotubes. First, an Fe / Ni alloy to be used as a metal catalyst is made by the following method. Nickel nitride and iron nitride are dissolved in distilled water at room temperature, followed by stirring with ammonium bicarbonate. The precipitate produced from this solution is washed with distilled water and ethanol and dried in vacuo. The dried precipitate is calcined in a dried air atmosphere at a temperature of 400 ℃ to form Fe-Ni oxide. The Fe—Ni oxide is reduced in a temperature of 400 ° C. and H ₂ / He atmosphere, and then worked up again at an ambient temperature of O ₂ / He to obtain a Fe-Ni alloy catalyst. The catalyst prepared in this way is placed in a quartz tube in a reactor and heat treated at 625 ° C. for 2 hours in an H 2 / He atmosphere. Thereafter, heat treatment is performed at 625 ° C. for 2 hours while flowing a mixed gas of CO / H ₂ to obtain carbon fibers.

The resulting carbon fiber is a structure in which a carbon hexagonal plane is formed parallel to the fiber axis and has a hollow inside the fiber. (Fig. 2) The outer diameter of the fiber is 5 to 35 nm, and the aspect ratio is 30 or more. FIG. 2A is a TEM image, FIG. 2B is an explanatory diagram illustrating a structure in which nano-branches are stacked, and FIGS. 2C and 2D are STM images of surfaces. One can observe the nano-branched connected stacked structure.

Second, fibrous nanocarbon with platelet structure. The Fe catalyst was prepared from iron nitride by the above-described method, placed in a quartz tube in a reactor, and heat-treated at 600 ° C. for 2 hours while flowing a CO / H ₂ mixed gas. The resulting carbon fiber is a platelet structure in which a carbon hexagonal plane is arranged in a direction perpendicular to the fiber axis. (FIG. 3) The diameter of the fiber is 90 to 300 nm and the aspect ratio is 30 or more. 3A and 3B are TEM images, FIG. 3C is an STM image of a surface, and FIG. 3D is an explanatory diagram illustrating a structure in which nano-branches are stacked. The structure where the nano-branches are stacked perpendicular to the fiber axis can be observed.

Third, fibrous nanocarbon of herringbone structure. Ni-Cu alloy catalyst was prepared from nickel nitride and copper nitride by the above-described method, placed in a quartz tube in a reactor, and heat-treated at 580 ° C. and H ₂ / He for 2 hours while flowing a mixed gas of ethylene / hydrogen, Obtain carbon fiber. The produced carbon fiber has a herringbone structure in which a carbon hexagonal plane has an angle of 20 to 80 ° in a V shape with respect to the fiber axis. (FIG. 4) The diameter of the fiber is 80 to 350 nm. Aspect ratio is 30 or more. 4A and 4B are TEM images, FIG. 4C is an STM image of a surface, and FIG. 4D is an explanatory diagram illustrating a structure in which nano-branches are stacked. One can observe the structure in which the nano-branches are stacked at an angle to the fiber axis.

Next, a method of manufacturing porous fibrous nanocarbon using the nano-drilling process of the present invention will be described.

Example 1

The herringbone fibrous nanocarbon is immersed and dispersed in a nickel nitride solution so that the nickel particles to be used as the nano-drill catalyst adhere to the outer circumferential surface of the herringbone fibrous nanocarbon. The fibrous nanocarbons are vacuum dried at 150 ° C. to produce nanofibers with a nickel catalyst. The fibrous nanocarbon attached with the nickel catalyst is placed in a quartz tube in a reactor, and heat-treated for 2 hours in a temperature H ₂ / He mixed gas atmosphere at 800 ° C.

The resulting porous fibrous nanocarbon is nanofibers that are very porous by forming nanotunnels, as shown in the TEM of FIG. 5. The nanotunnel is formed along the arrangement direction of the carbon hexagonal network layer without changing the structure of the fibrous nanocarbon, and the size of the nanotunnel is 5 to 30 nm in diameter. The specific surface area and the pore volume were measured by N ₂ Brunauer-Emmett-Teller (BET) method, respectively, 352 m 2 / g and 0.42 cm 3 / g.

Example 2

The herringbone fibrous nanocarbon is immersed and dispersed in a nickel nitride solution so that the nickel particles to be used as the nano-drill catalyst adhere to the outer circumferential surface of the herringbone fibrous nanocarbon. The fibrous nanocarbons are vacuum dried at 150 ° C. to produce nanofibers with a nickel catalyst. The fibrous nanocarbon attached with the nickel catalyst is placed in a quartz tube in the reactor, and heat-treated for 3 hours in a temperature O ₂ atmosphere of 350 ° C.

The resulting porous fibrous nanocarbon is nanofibers that are very porous by forming nanotunnels, as shown in the TEM of FIG. 6. The nanotunnel is formed along the arrangement direction of the carbon hexagonal network layer without changing the structure of the fibrous nanocarbon, and the size of the nanotunnel is 2 to 10 nm in diameter. The average size of the pores is smaller than that of Example 1, but more uniform than the distribution. The specific surface area and the volume of the pores were measured by N ₂ Brunauer-Emmett-Teller (BET) method, respectively, to be 298 m 2 / g and 0.39 cm 3 / g.

Example 3

The herringbone fibrous nanocarbon is immersed and dispersed in the iron nitride solution so that the iron particles to be used as nano-drill catalysts adhere to the outer circumferential surface of the herringbone fibrous nanocarbon. The fibrous nanocarbons were vacuum dried at 150 ° C. to produce nanofibers with an iron catalyst. The fibrous nanocarbon with an iron catalyst is placed in a quartz tube in a reactor, and heat-treated for 3 hours in a temperature He / H ₂ atmosphere of 850 ° C.

The resulting porous fibrous nanocarbon is a nanofiber, which is very porous due to the formation of a plurality of nanotunnels as shown in the TEM of FIG. 7, and the nanotunnels are formed along the arrangement direction of the carbon hexagonal mesh layer. However, unlike Examples 1 and 2, partial graphitization by the catalyst proceeds simultaneously with gasification by the catalyst, and the carbon structure around the pores is slightly changed, whereby a porous material having good graphitization around the pores is produced. . The specific surface area and the pore volume were measured by N ₂ Brunauer-Emmett-Teller (BET) method, respectively, to be 254 m 2 / g and 0.33 cm 3 / g.

Example 4

The platelet fibrous nanocarbon is immersed and dispersed in a nickel nitride solution so that the nickel particles to be used as the nano-drill catalyst adhere to the outer circumferential surface of the platelet fibrous nanocarbon. The fibrous nanocarbons are vacuum dried at 150 ° C. to produce nanofibers with a nickel catalyst. The fibrous nanocarbon attached with the nickel catalyst is placed in a quartz tube in the reactor, and heat-treated for 3 hours in a temperature H ₂ / He atmosphere of 800 ℃.

The resulting porous fibrous nanocarbon is nanofibers that are very porous by forming nanotunnels, as shown in the TEM of FIG. 8. The nanotunnel is formed along the arrangement direction of the carbon hexagonal network layer without changing the structure of the fibrous nanocarbon, and the size of the nanotunnel is 6 to 32 nm in diameter. The specific surface area and the volume of the pores were measured by N ₂ Brunauer-Emmett-Teller (BET) method, respectively, 154 m 2 / g and 0.24 cm 3 / g.

Comparative Example 1

The conventional alkali activation method was applied to the herringbone fibrous nanocarbon. It is placed on a pan containing a mixture of herringbone fibrous nanocarbon and KOH (nanofiber: KOH = 1: 4 w / w), and heat-treated for 2 hours in a H ₂ / He mixed gas atmosphere at a temperature of 850 ° C. in a reactor.

According to the TEM image, a certain portion of the graphite hexagonal mesh layer is removed in a ladder shape at regular intervals to observe the consumed change. The BET results show that the specific surface area is 866 m 2 / g, and micropores of 1.0 nm or less are well developed. Such alkali activation can be seen as inappropriate for selectively forming medium pores (meso pores) like the porous fibrous nanocarbon of the present invention.

Comparative Example 2

By dispersing the buty structured fibrous nanocarbon in the nickel nitride solution, the nickel particles to be used as nano-drill catalysts adhere to the outer circumferential surface of the herringbone fibrous nanocarbon. The fibrous nanocarbons are vacuum dried at 150 ° C. to produce nanofibers with a nickel catalyst. The fibrous nanocarbon attached with the nickel catalyst is placed in a quartz tube in the reactor, and heat-treated for 3 hours in a temperature H ₂ / He atmosphere of 800 ℃.

Unlike the above-described examples, the fibrous nanocarbons produced showed less than 5% of the weight change before and after the reaction, and it was found that the pores did not develop even in the TEM. The specific surface area and the pore volume were measured by N ₂ Brunauer-Emmett-Teller (BET) method, respectively, to be 122 m 2 / g and 0.21 cm 3 / g. It can be seen that the nano-drilling method according to the invention is not effective for tubular fibrous nanocarbons, ie carbon nanotubes. As a result of this comparative example, that is, the tubular structure in which the tip of the nano-branch is not exposed on the surface, the nano drilling method is not effective, and thus, the preparation of the tunnel-type pores by the nano drilling of the present invention shows that the nano- The catalyst attached to the tip of the branch appears to selectively gasify the surrounding nano-branches.

Comparative Example 3

Carbon black is immersed and dispersed in a nickel nitride solution so that the nickel particles to be used as nano-drill catalysts adhere to the carbon black. The carbon black is vacuum dried at 150 ° C. to produce carbon black with nickel catalyst. The carbon black to which the nickel catalyst was attached was placed in a quartz tube in a reactor, and heat-treated for 3 hours in a temperature H ₂ / He atmosphere of 800 ° C.

Carbon black has little weight change before and after the reaction, and it can be seen that the nano-drill method according to the present invention is not effective for carbon black.

Examples of applications of the porous fibrous nanocarbon prepared by the nano-drilling method of the present invention are as follows.

First is adsorbent and chromatography. Pores of the porous fibrous nanocarbon according to the present invention, since the longest path is about 200nm, about 2 seconds are consumed for the molecules to diffuse from one side of the pore to the other side. As such, the diffusion time is very short and very useful for adsorbents and chromatography. In particular, in the case of chromatography, it can be suitably used to separate biologically important molecules such as enzymes, steroids, alkaloids, hormones and proteins.

Second is a catalyst support. Due to the short diffusion path described above, it can be importantly applied to the conversion of high molecular materials such as synthesis of steroids and enzymes and purification of crude oil.

Third, it is an electrode for the electrochemical reaction. The fibrous nanocarbon according to the present invention is immersed in a solution of the catalyst metal to coat the catalyst metal, thereby forming an electrode on the surface of the porous fibrous nanocarbon. The material thus made is resistant to alkalis and acids and can therefore be applied to electrochemical reactions with harsh environments. For example, a coating of Pt-Ru catalyst can be used as a catalyst for methanol subsidiary in a methanol fuel cell. 9 shows methanol oxidation measured by a cyclic voltammogram using a Pt-Ru catalyst electrode coated with carbon fiber and an Ag / AgCl electrode.

As described in detail above, according to the present invention, a porous fibrous nanocarbon having a high porosity, a uniform size thereof, and pores having a size of 2 to 100 nm (mesopore size) can be obtained. Such porous fibrous nanocarbon may be variously applied as an adsorbent, a chromatography material, a catalyst support, and the like. On the other hand, in electrochemical applications requiring conductivity, the conductivity between the particles can be further improved by the fibrous form. In addition, since the solid having a medium size of pores has a nano-size diameter of the fibrous, not the particulate, there is an advantage that can eliminate the inconvenience in handling such as filtering.

Embodiments of the present invention described above and illustrated in the drawings should not be construed as limiting the technical spirit of the present invention. Those skilled in the art of the present invention can change and change the technical spirit of the present invention in various forms, and the improvement and modification are within the protection scope of the present invention as long as it is obvious to those skilled in the art. Will belong.

Claims (14)

 In the porous fibrous nanocarbon having pores formed in the fiber, The pores are porous fibrous nanocarbon, characterized in that the tunnel shape formed toward the fiber axis from the outer peripheral surface. The method of claim 1, The fibrous nanocarbon is a nanofiber of platelet structure in which a carbon hexagonal mesh layer is vertically stacked with respect to the fiber axis, and the pores are formed along the arrangement direction of the carbon hexagonal network layer. The method of claim 1, The fibrous nanocarbon is a herringbone structure of nanofibers having a carbon hexagonal netting layer having an angle of 20 to 80 ° with a V shape around the fiber axis, and the pores are formed along the arrangement direction of the carbon hexagonal netting layer. Porous fibrous nanocarbon. The method according to any one of claims 1 to 3, The nanofibers have a diameter of 2 to 500nm, and the aspect ratio is 4 or more porous fibrous nano-carbon. The method according to any one of claims 1 to 3, The pore size is 2 to 100nm, porous fibrous nanocarbon, characterized in that it has a porosity of at least 20% or more. By attaching a substance containing a metal catalyst to the outer circumferential surface of the fibrous nanocarbon, and removing the carbon hexagon netting layer by gasification with the metal catalyst to form tunnel-shaped pores from the outer circumferential surface toward the fiber axis, the fibrous nanocarbon having pores Porous fibrous nanocarbon manufacturing method characterized in that it is prepared. The method of claim 6, Wherein said metal catalyst comprises at least one element selected from elements of the group consisting of groups V, VI, VII and VIII on the periodic table. The method of claim 7, wherein The metal catalyst is Fe, Ni, Cu, Pt, Mn, V and a method for producing a porous fibrous nano-carbon, characterized in that selected from among them. The method of claim 6, The tunnel-shaped pores are porous fibrous nanocarbon manufacturing method, characterized in that the specific portion of the fibrous nanocarbon attached with the metal catalyst is formed by the selective gasification reaction by the metal catalyst. The method of claim 9, By the selective reaction, as the carbon hexagonal net surface layer of the specific portion to which the metal catalyst is attached, the pores are formed along the arrangement direction of the carbon hexagonal net surface layer, the porous fibrous nano-carbon manufacturing method. The method of claim 6, The reactant for gasification of the carbon hexagonal mesh layer by the metal catalyst comprises a hydrogen-fiber porous carbon nanocarbon manufacturing method, characterized in that. The method of claim 11, The gasification temperature is a porous fibrous nano-carbon manufacturing method, characterized in that 500 to 900 ℃. The method of claim 6, The reactant for gasification of the carbon hexagon mesh face layer by the metal catalyst comprises an oxidizing gas. The method of claim 13, The activation temperature is a porous fibrous nano-carbon manufacturing method, characterized in that 200 to 400 ℃.

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