KR20170092351A - Method of singlewall carbon nanotube separation and composition including singlewall carbon nanotube - Google Patents

Abstract

A method for separating a single-walled carbon nanotube of the present invention comprises the following steps: preparing a single-walled carbon nanotube dispersion containing the single-walled carbon nanotube, a flavin derivative, and a nonpolar solvent; ultrasonically treating the single-walled carbon nanotube dispersion; and carrying out centrifugation of the ultrasonically treated single-walled carbon nanotubes by using a supernatant solution containing a semiconductive single-walled carbon nanotube and a precipitation solution containing a metallic single-walled carbon nanotube to form a separation solution, thereby obtaining semiconductive or metallic single-walled carbon nanotubes capable of mass production and having high purity.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for separating single-walled carbon nanotubes,

The present invention relates to carbon nanotubes, and more particularly, to a method for separating single-walled carbon nanotubes and a composition including single-walled carbon nanotubes.

Carbon nanotubes (CNTs) are anisotropic and can have a variety of structures. For example, the carbon nanotubes can be single-walled, multi-walled, or bundled. Also, since it has a diameter of nanometer, it can be applied to various fields.

Among them, single-walled carbon nanotubes (SWNTs) defined by a chiral (n, m) vector with a graphen sheet wrapped in a cylindrical shape have excellent electrical, mechanical and optical properties And can be applied to various fields. Single-walled carbon nanotubes exhibit conductor or semiconductor properties depending on their chirality. In this case, single-walled carbon nanotubes are mixed with semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes. In the case of an arm-chair structure, they are metallic, while when they are zig-zag structures Semiconducting. In particular, semiconducting single-walled carbon nanotubes have a quasi-one-dimensional structure in which the energy gap varies depending on the diameter, thereby exhibiting a specific quantum effect.

In order to apply such a single-walled carbon nanotube application technology, a process of obtaining a single-walled carbon nanotube having a specific chirality characteristic is required. For example, semiconducting single-walled carbon nanotubes must be manufactured for application to memory devices, sensors, and the like. In addition, metallic single-walled carbon nanotubes are required to be applied to cell electrode materials, electromagnetic shielding agents, and the like.

However, chemical vapor deposition (CVD) is the most common method for producing single-walled carbon nanotubes. When using a CVD process, it is difficult to selectively produce single-walled carbon nanotubes having desired chiral properties . Accordingly, a single-walled carbon nanotube is generally grown in the form of a mixture of semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes. Thereafter, the separation process of separating the semiconducting single-walled carbon nanotubes and the metallic single-walled carbon nanotube is suitably applied to the application field.

Conventionally, a single-walled carbon nanotube is dispersed in a solution by separating a semiconducting single-walled carbon nanotube and a metallic single-walled carbon nanotube, followed by separating the metallic single-walled carbon nanotube by electrophoresis However, since the yield is low, it is not suitable for mass production, and since the purity is low, a separate additional separation step is required.

In the past, a method of separating semiconducting single-walled carbon nanotubes from a mixture of semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes by using a surfactant has been proposed. However, this method also has disadvantages . In addition, the single-walled carbon nanotubes have a disadvantage that they are aggregated in the mixed solution because of low dispersibility.

Therefore, there is an urgent need to develop a method which is suitable for mass production, improves the dispersibility of single wall carbon nanotubes, and can separate semiconducting or metallic single wall carbon nanotubes with high purity.

KR 2015-0001354 A

Disclosure of the Invention The present invention has been conceived to solve the above-described problems, and it is an object of the present invention to provide a method for separating single-walled carbon nanotubes which are suitable for mass production, improve dispersibility of single-walled carbon nanotubes, The present invention provides a method for separating single-walled carbon nanotubes from a single-walled carbon nanotube.

Another object is to provide a high purity functionalized single-walled carbon nanotube composition.

One aspect of the present invention provides a method for separating semiconducting single-walled carbon nanotubes from single-walled carbon nanotubes. The separation method comprises the steps of: preparing a single-walled carbon nanotube dispersion including a single-walled carbon nanotube, a flavin derivative, and a non-polar solvent; ultrasonifying the single-walled carbon nanotube dispersion; Separating the carbon nanotubes by a supernatant containing semiconductive single wall carbon nanotubes and a metallic single wall carbon nanotube; And purifying the semiconducting single-walled carbon nanotube from the supernatant.

Another aspect of the present invention provides a method for separating metallic single-walled carbon nanotubes from single-walled carbon nanotubes. The separation method comprises the steps of: preparing a single-walled carbon nanotube dispersion including a single-walled carbon nanotube, a flavin derivative, and a non-polar solvent; ultrasonifying the single-walled carbon nanotube dispersion; Separating the carbon nanotubes by a supernatant containing semiconductive single wall carbon nanotubes and a metallic single wall carbon nanotube; And purifying the metal single walled carbon nanotube from the precipitating solution.

In one preferred embodiment of the present invention, the mass ratio of the single walled carbon nanotube and the flavin derivative may be 1: 0.5 to 1: 1.5.

In one preferred embodiment of the present invention, the Flavin derivative is selected from the group consisting of Flavin mononucleotide (FNP), flavin adenine dinucleotide (FAD), 10-dodecyl isoalloxazine, and riboflavin And < / RTI >

In a preferred embodiment of the present invention, the non-polar solvent may include at least one selected from the group consisting of xylene, xylene isomers, benzene, and toluene.

In a preferred embodiment of the present invention, the flavin derivative is 10-dodecyl-isoyloxazine and the nonpolar solvent may be p-xylene.

In a preferred embodiment of the present invention, in the second step, the ultrasonic treatment may be performed by irradiating ultrasonic waves for 1 to 60 minutes at a speed of 1 to 750 W.

In a preferred embodiment of the present invention, in the step 3, the centrifugation may be performed at a speed of 1,000 to 50,000 g for 1 to 3 hours.

Another aspect of the present invention provides a composition comprising semiconducting single walled carbon nanotubes. The composition comprises a semiconducting single-walled carbon nanotube, a reduced Flavin derivative, and a nonpolar solvent, wherein the purity is greater than 95%.

Another aspect of the present invention provides a composition comprising metallic single walled carbon nanotubes. The composition comprises a metallic single walled carbon nanotube, a reduced Flavin derivative, and a nonpolar solvent, wherein the purity is greater than 70%.

According to the method for separating single-walled carbon nanotubes according to the present invention, mass production is possible and dispersion of single-walled carbon nanotubes can be improved. Further, there is an effect that the single-walled carbon nanotube having semiconductivity or metallicity can be separated at a high purity.

In addition, the composition including the single-walled carbon nanotube according to the present invention can provide a high-purity semiconducting single-walled carbon nanotube composition and a metallic single-walled carbon nanotube composition applicable to various fields.

1 is a schematic view illustrating a method of separating a single-walled carbon nanotube according to an embodiment of the present invention.
FIG. 2 is a graph showing the wavelength-absorption spectrum (A) of the supernatant and precipitate in the separation solution of Example 1 of the present invention and the separation solution of Comparative Example 1, and the graphs of the single-walled carbon nanotubes of Examples 1 and 5 Of Raman spectra (B).
3 is a graph showing PLE characteristics of the supernatant of Example 1 of the present invention.
4 is a graph showing the absorption spectra of the supernatants of Examples 1 to 4. Fig.
5 is a graph showing PLE characteristics of Production Examples 1 to 4.
6 is a graph showing the absorption spectra of the supernatants of Comparative Examples 2 to 5 according to the centrifugal force.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Like reference numerals designate like elements throughout the specification.

1 is a schematic view illustrating a method of separating a single-walled carbon nanotube according to an embodiment of the present invention.

Referring to FIG. 1, a method for separating a semiconducting single-walled carbon nanotube from a single-walled carbon nanotube according to an embodiment of the present invention includes a single-walled carbon nanotube, a flavin derivative, Preparing a dispersion of carbon nanotubes, ultrasonically treating the single-walled carbon nanotube dispersion, separating the supersonicized single-walled carbon nanotube into a supernatant containing semiconductive single-walled carbon nanotubes and a metallic single-walled carbon nanotube To form a separation solution, and purifying the semiconducting single-walled carbon nanotube from the supernatant.

The preparation of the single-walled carbon nanotube dispersion will be described. The single wall carbon nanotube dispersion includes single wall carbon nanotubes, flavin derivatives, and non-polar solvents.

The properties of the single walled carbon nanotubes vary depending on their chiralities. In the case of an arm-chair structure, the single-walled carbon nanotubes exhibit metallicity. When they have a zig-zag structure, they exhibit semiconducting properties. Thus, the single-walled carbon nanotubes include semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes. The diameter of the single walled carbon nanotube may be 0.5 to 2.0 nm, but is not limited thereto.

The Flavin derivatives serve to disperse the single-walled carbon nanotubes in a solvent. The Flavin derivative may include one or more selected from the group consisting of FMN (Flavin mononucleotide), FAD (flavin adenine dinucleotide), 10-dodecyl isoalloxazine, and riboflavin have. In particular, when the Flavin derivative is 10-dodecyl-isoalloc photo, the dispersion effect on the single-walled carbon nanotubes is excellent and it facilitates the formation of the separated solution by the ultrasonic treatment process and centrifugation which will be described later.

The nonpolar solvent may include at least one selected from the group consisting of xylene, xylene isomer, benzene, and toluene. Particularly, when the non-polar solvent is p-xylene, p-xylene has excellent solubility in the single-walled carbon nanotube and flavin derivative, so that the effect of separating carbon nanotubes can be further improved.

Also, the non-polar solvent may be 10-dodecyl-isoalloc, and when the non-polar solvent is p-xylene, the separation effect of the single-walled carbon nanotubes may be the most excellent in improving the separation efficiency of carbon nanotubes within the range of the materials described above.

The mass ratio of the single-walled carbon nanotube and the flavin derivative may be 1: 0.5 to 1.5, and more preferably 1: 0.8 to 1.2. If the mass ratio of the single-walled carbon nanotube and the Frabin derivative is less than 1: 0.5, the dispersion of the single-walled carbon nanotube dispersion may be lowered. If the ratio is more than 1: 1.5, Can be lowered.

Next, the single-walled carbon nanotube dispersion is subjected to ultrasonic treatment. At this time, by the ultrasonic treatment, the isoalloxazine of the flavin derivative and the single-walled carbon nanotube are weakened due to the pi-pi interactions. Thus, the semiconducting carbon nanotube and the metallic carbon nanotube are separated from the single-walled carbon nanotube dispersion. Therefore, the single wall carbon nanotube dispersed in the nonpolar solvent through the ultrasonic treatment can be separated into the supernatant and the precipitate. Accordingly, the intensity of the ultrasonic wave in the ultrasonic wave processing step described later can be lowered and the time can be reduced. Further, the centrifugal separation rate can be lowered in the centrifugal separation process for forming a separation solution, which will be described later, and the time can be shortened.

The ultrasonic treatment may be performed by irradiating ultrasonic waves for 1 to 60 minutes at a intensity of 1 to 100 W, and more preferably for 1 to 10 minutes at an intensity of 50 to 80 W. When the intensity of the ultrasonic waves is less than 1 W, the process time for separating the single wall carbon nanotubes into the supernatant liquid and the settling liquid can be prolonged, and when the intensity of the ultrasonic waves exceeds 100 W, the semiconductive or metallic single wall carbon The purity of the nanotubes can be lowered. When the ultrasonic treatment time is less than 1 minute, the probability of not separating the single wall carbon nanotube into a supernatant and a settling solution increases, and when the ultrasound treatment time exceeds 60 minutes, the purity of the semiconductive or metallic single wall carbon nanotubes Can be lowered.

Next, the single-walled carbon nanotube is centrifuged with a needle solution containing a supernatant containing semiconductive single-walled carbon nanotubes and a metallic single-walled carbon nanotube to form a separated solution. The centrifugation may be performed at a rate of 1,000 to 50,000 g (g = 9.8 m / s ² ) for 1 hour to 3 hours, more preferably at a rate of 3,000 to 7,000 g for 1.5 to 2.5 hours . If the centrifugation speed is less than 1,000 g, the process time for separating the single-walled carbon nanotube into the supernatant and the sediment can be prolonged. If the centrifugation speed is more than 50,000 g, the purity of the semiconductive or metallic single-walled carbon nanotube Can be lowered.

At this time, the separation solution includes a semiconductor single-walled carbon nanotube, a reduced Flavin derivative, and a non-polar solvent, and has a purity of 95% or more.

Next, the semiconducting single-walled carbon nanotube is purified from the supernatant. At this time, the step of separating the supernatant from the separation solution can be used without limitation as long as the supernatant is a process capable of separating the supernatant from the supernatant and the supernatant separated from the supernatant. For example, the supernatant may be removed from the separation solution to separate the supernatant and the sediment. Further, the separation solution may be immersed in a container having an opening at one side of the lower end thereof, and then the supernatant solution and the sedimentation solution may be separated by discharging only the sedimentation solution through the opening, but the present invention is not limited thereto.

Thereafter, the separated supernatant is purified to obtain semiconducting single-walled carbon nanotubes. At this time, the method for purifying the semiconducting single-walled carbon nanotubes from the supernatant may use various known methods without limitation as long as it is a method for purifying suspended solids in a solution. For example, the semiconducting single-walled carbon nanotubes suspended in the supernatant can be removed using a sieve network, but the present invention is not limited thereto.

1, a method for separating a metallic single-walled carbon nanotube from a single-walled carbon nanotube according to an embodiment of the present invention includes a single-walled carbon nanotube, a flavin derivative, and a single Preparing a wall carbon nanotube dispersion, ultrasonically treating the single wall carbon nanotube dispersion, separating the ultrasonic treated single wall carbon nanotube into a supernatant containing semiconductive single wall carbon nanotubes and a metallic single wall carbon nanotube Centrifuging the solution with a sedimentation liquid containing a tube to form a separation solution, and purifying the metal single walled carbon nanotube from the sedimentation liquid.

At this time, the step of preparing the single-walled carbon nanotube dispersion, the step of ultrasonication, and the step of forming the separation solution are the same as the method of separating the semiconducting single-walled carbon nanotubes from the single-walled carbon nanotubes described above, I will refer to the contents.

Next, the metallic single-walled carbon nanotube is purified from the precipitate. At this time, the step of separating the precipitating solution from the separation solution can be used as long as it is a process capable of separating the precipitating solution from the separation solution separated by the supernatant and the precipitating solution, among the known techniques. For example, the supernatant may be removed from the separation solution to separate the supernatant and the sediment. Further, the separation solution may be immersed in a container having an opening at one side of the lower end thereof, and then the supernatant solution and the sedimentation solution may be separated by discharging only the sedimentation solution through the opening, but the present invention is not limited thereto.

Thereafter, the separated precipitating solution is purified to obtain semiconducting single-walled carbon nanotubes. At this time, the step of purifying the metallic single-walled carbon nanotubes may further include the steps of: preparing a mixed solution of metallic single-walled carbon nanotubes by further adding a flavin derivative and a non-polar solvent to the precipitating solution; And ultrasonic treatment of the mixed solution. At this time, since the flavin derivative and the nonpolar solvent have the same materials and composition as the flavin derivative and the nonpolar solvent described above, the above description will be referred to.

The ultrasound treatment of the metal single wall carbon nanotube mixed solution may be performed by ultrasonic treatment under the same conditions as the ultrasound treatment of the single wall carbon nanotube dispersion described above.

Through such a process, a metallic single-walled carbon nanotube composition containing metallic single wall carbon nanotubes, reduced flavin derivatives, and non-polar solvents and having a purity of 70% or more can be obtained.

The method for purifying the metal single walled carbon nanotubes from the composition containing the metallic single walled carbon nanotubes may be various methods known in the art for purifying suspended solids in the solution. For example, the metal single walled carbon nanotubes floating on the inherent single walled carbon nanotube composition may be removed using a filtering network, but the present invention is not limited thereto.

Hereinafter, exemplary embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are intended to aid understanding of the present invention, and the present invention is not limited by the following experimental examples.

Example  One- Semiconducting Single wall  Carbon nanotube separation

1 mg of a single wall carbon nanotube (SWNT / length distribution: 0.5 to 4 탆, SWNT content: 30 to 70%), 10-dodecyl isoalloxazine (F12 ), And 4 ml of p-xylene as a non-polar solvent.

Next, the single-walled carbon nanotube dispersion was ultrasonicated for 5 minutes in a Branson 1510 sonicator (70 W), and further tip communication (40% power (18.8 W / mL) Diameter: 13 mm, VCX 750, Sonics & Materials) was cooled to 10 ° C with a water circulator and cooled for 1 hour.

Next, the ultrasonically treated single-walled carbon nanotube was immersed in a centrifuge (No. 1 fixed-angle rotor, Supra 22K, Hanil or Wisespin CF-10, Daihan Scientific Co., Ltd) A centrifugation process was performed with a separation solution containing supernatant containing semiconducting single wall carbon nanotubes and metallic single wall carbon nanotubes.

Thereafter, 80 wt% of the semiconducting single-walled carbon nanotubes (s-SWNTs) present in the supernatant liquid as floating matters was removed to obtain semiconducting single-walled carbon nanotubes.

Example  2 to 4

Except that the centrifugal separation rate was changed to 10,000 g, 20,000 g and 30,000 g in Examples 2, 3 and 4, respectively, in the same manner as in Example 1, A tube was obtained.

Example  5

After the separation solution was formed under the same conditions as in Example 1, the supernatant was discharged so that only the precipitate containing the metallic single-walled carbon nanotube (m-SWNT) remained in the separation solution. Then, 4 mg of FC12 and 4 mL of p-xylene were added to the remaining m-SWNT precipitate. Thereafter, ultrasonic treatment was performed at a room temperature for 1 hour using a tip sonication at an ultrasonic intensity of 18.8 W / mL.

compare Example  One

1 mg of SWNT, 10 mg of surfactant SDS (sodium dodecyl sulfate), and 10 mL of water was prepared.

Thereafter, the mixed solution was subjected to ultrasonic treatment for 1 hour using the bathersonization used in Example 1, and then subjected to ultrasonic treatment for 5 hours using the tip sonication (300 W) used in Example 1.

Thereafter, centrifugation was performed at 80,000 g for 10 hours using a centrifuge (70 Ti rotor, Beckman Coulter) to prepare a separation solution.

Then, to remove the SWNT bundle, the carbonaceous substance and the metallic impurities in the separation solution under the condition of pH 10, 80 wt% of the suspension was floated to obtain semiconducting single-walled carbon nanotubes.

compare Example  2 to 5

1 mg of SWNT, 1 mg of surfactant SDS (sodium dodecyl sulfate), and 4 mL of water was prepared.

Thereafter, the mixed solution was subjected to ultrasonic treatment under the same conditions as in Example 1, followed by centrifugation (5000, 10000, 20000, 30000 g ) under the same conditions as in Examples 1 to 4, respectively, did.

< Experimental Example  One - PLE  Measurement>

Fluorescence spectroscopy measurements were carried out on a Spex Nanolog 3-211 spectrofluorometer (Horiba, Calif.) Equipped with a single-channel InGaAs array detector (512 x 1 pixel, measuring range 800 to 1650 nm), excited by a broadband 450 W xenon lamp and cooled with liquid nitrogen Jobin-Yvon). A grating of 150 gr / mm was used to disperse the emitted light. The slits of the excitation and emission portions were set at 14 and 10 nm. The intensity of the excitation and emission are all calibrated with the sensitivity correction factor used to make the PLE map. The PL chirality placement of the s-SWNT was based on the PL pattern fit of the PLE map published by O'ConnellS13. To precisely locate the S ₁₁ and S ₂₂ positions of FC12-SWNTs dispersed with p-xylene, excitation and emission from a given PL location near the PLE map were deconvoluted into a Lorentzian shape.

< Experimental Example  2 - Measurement of UV and Raman properties>

The UV and Raman characteristics of the semiconductive or metallic single-walled carbon nanotubes of Production Examples 1 to 5 and Comparative Production Example 1 were measured. Raman spectra were obtained using LabRam ARAmis (Horiba Jobin Yvon). Scattered light was obtained through backscattering geometry using 100 × objective and 600 gr / mm grating. The laser intensity for the Raman measurement was 0.7 mW, in order to prevent damage to unwanted SWNTs. 632.8 nm and 785 nm lasers were used to analyze HiPco and SWNT, respectively. Si ^peak-a (520.89 cm ¹⁾ was used as an internal test. (Sample preparation conditions: tens of microliters of dispersed SWNTs were deposited on Si substrates washed with Piranha solution.) Extra FC12 was removed by washing several times with methanol until no green PL caused by FC12 appeared. )

< Experimental Example  3 - LC-MS measurement>

LC-MS spectra were measured using 1260 Infinity LC / 6530 and Accurate Q-TOF (Agilent Technologies).

< Experimental Example  4 - AFM  Measurement>

The AFM measurement was performed with an AFM (Nanowizard I, JPK instrument) installed on an inverted microscope (Zeiss). Silicon AFM cantilevers coated with aluminum (spring constant: 13-77 N / m, oscillation range: 200-400 kHz, AppNano) were used for tapping mode imaging and the pixel size was 512x512.

2 is a graph showing the wavelength-absorbance spectra (A) of the s supernatant and the precipitate in the separation solution of Example 1 of the present invention and of the separation solution of Comparative Example 1 and the single-walled carbon nanotubes of Example 1 and Example 5 Raman spectra (B) of the tube.

At this time, the Raman spectrum represents a radical breathing mode (RBM).

Referring first to FIG. 2 A, it can be seen that there is a strong peak in the S ₂₂ and S ₁₁ regions of the supernatant of Example 1. Therefore, it is predicted that the supernatant contains semiconducting single-walled carbon nanotubes and exhibits high purity. On the other hand, it can be seen that a strong peak is present in the M ₁₁ region in the precipitate of Example 1. In addition, it can be seen that a peak is also present in the S ₂₂ and S ₁₁ regions of the precipitate, which may be a peak due to the carbon impurities remaining in the precipitate. In addition, in the case of the separation solution of Comparative Example 1, peaks were present in the M ₁₁ and S ₂₂ regions but the peak characteristics were insignificant, and the peak characteristics were not observed in the S ₁₁ region. It can be seen that Comparative Example 1 did not cause selective separation according to the electrical properties.

Referring to FIG. 2B, it can be seen that in the case of the supernatant of Example 1, strong peaks are present in the S ₂₂ and S ₁₁ regions. Therefore, it is predicted that the supernatant contains semiconducting single-walled carbon nanotubes and exhibits high purity. On the other hand, it can be seen that a strong peak is present in the M ₁₁ region in the precipitate of Example 1.

3 is a graph showing PLE characteristics of the supernatant of Example 1 of the present invention.

Table 1 below is a table showing the positions of S ₁₁ and S ₂₂ and the diameter of SWNT for the PLE graph. At this time, the diameter of the SENT was calculated as 1.44 A CC bonding length.

Assignment
( n, m ) Diameter
(nm) Optical transitions S ₁₁ (nm) S ₂₂ (nm) (6, 5) 0.76 986.7 581.9 (8,3) 0.78 980.8 673.8 (7, 5) 0.83 1044.9 656.9 (8,4) 0.84 1124.6 605.8 (10, 2) 0.88 1069.0 751.2 (7, 6) 0.90 1147.4 662.0 (9, 4) 0.92 1118.6 736.3 (11, 1) 0.92 1303.3 624.3 (10, 3) 0.94 1273.9 645.4 (8, 6) 0.97 1205.7 734.0 (9, 5) 0.98 1269.2 689.5 (11,3) 1.01 1217.6 823.4 (13,0) 1.03 1418.3 687.8 (8, 7) 1.03 1308.1 741.6 (10,5) 1.05 1280.9 823.8 (11,4) 1.07 1413.1 729.9 (9, 7) 1.10 1369.6 825.6 (10, 6) 1.11 1420.1 765.8 (13,2) 1.12 1334.6 883.4 (12, 4) 1.15 1383.4 883.1 (9,8) 1.17 1458.7 829.4 (11, 6) 1.19 1432.4 884.9 (15,1) 1.23 1463 940 (10,8) 1.24 1512.7 889.1 (14,3) 1.25 1489.8 941.9 (13,5) 1.28 1534.6 936.6

Referring to FIG. 3 and Table 1, it can be seen that the s-SWNT content of the supernatant containing s-SWNT is concentrated to a purity of about 96%. As a result, the method of separating the semiconducting single-walled carbon nanotube from the single-walled carbon nanotube according to an embodiment of the present invention can separate the semiconducting single-walled carbon nanotube with high purity.

4 is a graph showing the absorption spectra of the supernatants of Examples 1 to 4. Fig.

4, it can be seen that the absorption peak of Example 1 having a centrifugal force of 5000 g is the strongest.

5 is a graph showing PLE characteristics of Production Examples 1 to 4.

Referring to FIG. 5, it can be seen that the purity of s-SWNT of Production Example 4 having the highest centrifugal force is the highest.

6 is a graph showing the absorption spectra of the supernatants of Comparative Examples 2 to 5 according to the centrifugal force.

Referring to FIG. 6, in Comparative Examples 2 to 5, it was confirmed that the absorption peak did not appear clearly and the separation of semiconducting property and metallic property was not achieved as compared with Examples 1 to 4 because of poor dispersion. This may be because the critical micelle concentration is not met.

As a result, it can be seen that the dispersion and separation of SWNTs in Comparative Examples 2 to 5 are not properly performed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that the present invention, Various modifications and variations are possible.

Claims (11)

Preparing a single walled carbon nanotube dispersion comprising a single wall carbon nanotube, a flavin derivative, and a nonpolar solvent;
Ultrasonically treating the single-walled carbon nanotube dispersion;
Separating the ultrasonically treated single walled carbon nanotube into a precipitating solution containing a supernatant containing semiconductive single walled carbon nanotubes and a metallic single walled carbon nanotube to form a separated solution; And
And purifying the semiconducting single-walled carbon nanotube from the supernatant. The method of separating a semiconducting single-walled carbon nanotube from a single-walled carbon nanotube. Preparing a single walled carbon nanotube dispersion comprising a single wall carbon nanotube, a flavin derivative, and a nonpolar solvent;
Ultrasonically treating the single-walled carbon nanotube dispersion;
Separating the ultrasonically treated single walled carbon nanotube into a precipitating solution containing a supernatant containing semiconductive single walled carbon nanotubes and a metallic single walled carbon nanotube to form a separated solution; And
And purifying the metallic single-walled carbon nanotube from the precipitating solution. 2. A method for separating a metallic single-walled carbon nanotube from a single-walled carbon nanotube comprising: 3. The method according to claim 1 or 2,
Wherein the mass ratio of the single-walled carbon nanotube to the Frabin derivative is 1: 0.5 to 1.5. 3. The method according to claim 1 or 2,
Wherein the Flavin derivative is at least one selected from the group consisting of FMN (Flavin mononucleotide), FAD (flavin adenine dinucleotide), 10-dodecyl isoalloxazine, and riboflavin How to separate wall carbon nanotubes. 3. The method according to claim 1 or 2,
Wherein the non-polar solvent comprises at least one selected from the group consisting of xylene, xylene isomers, benzene, and toluene. 3. The method according to claim 1 or 2,
Wherein the Flavin derivative is 10-dodecyl-isoalloc photo, and the non-polar solvent is p-xylene. 3. The method according to claim 1 or 2,
In the ultrasound treatment, the ultrasonic treatment is performed by irradiating ultrasonic waves for 1 to 60 minutes at 1 to 100 W intensity, thereby separating the single-walled carbon nanotubes. 3. The method according to claim 1 or 2,
Wherein the centrifugal separation is performed at a speed of 1,000 to 50,000 g for 1 to 3 hours in the step of forming the separation solution. 3. The method of claim 2,
The step of purifying the metal single walled carbon nanotubes comprises:
Preparing a mixed solution of metal single wall carbon nanotubes by further adding a flavin derivative and a nonpolar solvent to the precipitating solution; And
And subjecting the metal single wall carbon nanotube mixed solution to ultrasonic treatment. A semiconducting single-walled carbon nanotube comprising semiconducting single-walled carbon nanotubes, reduced flavin derivatives, and nonpolar solvents, wherein the semiconducting single-walled carbon nanotubes have a purity of 90% or greater. A composition comprising metallic single-walled carbon nanotubes, reduced single-walled carbon nanotubes, reduced flavin derivatives, and non-polar solvents, wherein the metallic single-walled carbon nanotubes have a purity of greater than 70%.

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