WO2008147004A1

WO2008147004A1 - Manufacturing method of fullerene manifold

Info

Publication number: WO2008147004A1
Application number: PCT/KR2007/006107
Authority: WO
Inventors: Jung Sun Ahn; Seung Jun Yeo; Chin Ho Shin; Jung Yun Jo; So Ra Park
Original assignee: Industry Academic Cooperation Foundation Of Kyunghee University
Priority date: 2007-05-30
Filing date: 2007-11-29
Publication date: 2008-12-04

Abstract

The present invention relates to a manufacturing method of fullerene manifold and more particularly, provides the method comprising generating solution droplets of micrometer size from fullerene monomers and making fullerene assembly through condensation process of fullerene monomers due to concentration of solute by natural evaporation of solvent in a vacuum and progressing photo-polymerization reaction by irradiating UV and the like to the fullerene assembly.

Description

Description MANUFACTURING METHOD OF FULLERENE MANIFOLD

Technical Field

[1] The present invention relates to a manufacturing method of fullerene manifold having a characteristic of white photoemission, and more particularly, provides the method comprising steps of generating solution droplets of micrometer size from fullerene monomers, making fullerene assembly through condensation process of fullerene monomers due to concentration of solute by natural evaporation of solvent in a vacuum and progressing photo-polymerization reaction by irradiating UV and the like to the fullerene assembly. Background Art

[2] A fullerene is a substance consisted of carbon only, and has an intermediate structure between a graphite structure and a diamond structure. The fullerene is formed mainly with hexagonal rings, and partially with pentagonal rings.

[3] In relation to the fullerene, substances which are obtained by replacing some carbon atoms in the fullerene with other elements, or by adding other elements to the fullerene have also been well known. In addition, substances obtained by arranging metal atoms inside ball-shaped fullerene, and by arranging metals containing oxygen between fullerene molecules have also been well known.

[4]

[5] Typical fullerene is C , and C , C , C , C , C , C , C , and C , have also been 60 70 76 78 82 84 240 540 720 known. Each of the fullerenes has a ball shape of which the inside is empty. Also, tube shaped fullerenes have been known. In the ball or tube type fullerenes, the ball-state fullerenes are more significant and fullerenes according to the present invention will now be explained in the basis of the ball shaped fullerenes.

[6]

[7] The fullerene exists as solution or a single crystal. Solvents dissolving the fullerene may be benzene, toluene, CS , acetone, tricloroethylene, chlorobenzene, etc. The fullerene has a degree of freedom of rotation both as solution and as a single crystal. For example, in a single crystal at room temperature, a fullerene molecule, i.e., a fullerene monomer, does not have only the degree of freedom of translation, but rotates by a thermal motion. This relates to the fact that the fullerene has an isotropic ball shape in which the bonding between fullerene molecules is weak and the anisotropy of the potential of the bonding is small. Accordingly, the bonding between fullerene molecules in a solid body is mainly Van der Waals bonding by the interaction between Jt (pi) electrons. [8] As an application of the fullerene, lithography has been noted. Since the fullerene has a sublimation property and can form a thin film, if a latent image can be formed and developed on the thin film, the fullerene can be applied for lithography.

[9]

[10] Conventional method of making fullerene assembly for manufacturing fullerene manifolds is to make fullerene assembly spontaneously in the freezing process of fullerene solution dissolved in a single solvent such as toluene, benzene, CS , or to make fullerene assembly in solution at room temperature by mixing fullerene soluble solution and fullerene insoluble solution.

[11] However, there is a problem that the amount of fullerene manifolds having a charateristic of white photoemission gained from fullerene assembly above is extremely little, because light is irradiated in the condition that solution is freezed, in the case that fullerene manifold is generated by photo-polymerization reaction induced by irradiating UV laser on fullerene assembly formed in a single solvent.

[12] In addition, there is another problem that it is hard to generate 3-dimensional structured fullerene manifold having a characteristic of white photoemission because it has a size of several hundreds nanometer in the case of fullerene assembly generated at room temperature using indissoluble solvent. Disclosure of Invention

Technical Problem

[13] To solve these problems, the present invention provides a method of getting a great quantity of fullerene assembly for manufactuing fullerene manifolds easily by generating solution droplets of micrometer size from fullerene monomers dissolved solution, and making fullerene assembly by natural evaporation of the solution droplets in a vacuum.

[14] Also, the present invention provides the manufacturing method of fullerene manifold by photo-polymerization reaction induced by irradiating UV laser and the like to the fullerene assembly. Technical Solution

[15] According to an aspect of the present invention, there is provided a method of manufacturing a fullerene manifold having a characteristic of white photoemission, the method comprsing steps of generating fullerene solution by dissolving a fullerene monomers in a single solvent, spraying the fullerene solution into solution droplets of micrometer size, and making fullerene assembly by natural evaporation of the solution droplets of fullerene in a vacuum.

[16] According to another aspect of the present invention, there is also provided a method of manufacturing a fullerene manifold having a characteristic of white photoemission , the method comprising steps of inducing photo-polymerization reaction by irradiating UV laser to the fullerene assembly, and capturing the fullerene assembly in liquid state. [17]

Advantageous Effects

[18] As stated above, a great amount of fullerene assembly can be gained easily by making solution droplets of micrometer size from fullerene monomer dissolved solution and evaporating them to make fullerene assembly in a vacuum, according to the present invention.

[19] Also, after the fullerene assembly is made, an amount of fullerene manifolds having a characteristic of white photoemission can be gained by photo-polymerization reaction induced from irradiating UV laser.

[20] Also, a great quantity of fullerene manifolds can be made easily, since the generation of fullerene manifolds is possible by only irradiating UV laser to the fullerene assembly made by micro- spraying method, .

[21] Also, according to the present invention, it is possible to generate 3-dimensional structured fullerene manifold in a scale of nanometer which can not be gained from the fullerene manifold manufactured with usual bulk material using light, pressure and doped metal, and the 3-dimensional structured fullerene manifold can be applied to various display devices requiring white photoemission characteristic. Brief Description of the Drawings

[22] FIG. 1 to 4 are graphs illustrating measurments of UV absorption spectrum of fullerene solution after micro- spraying and photo-polymerizing in several concentration of the fullerene monomer solution according to an embodiment of the present invention.

[23] FIG. 5 is a graph illustrating HPLC measurments of fullerene monomers.

[24] FIG 6 is a graph illustrating HPLC measurments of fullerene solution after micro- spraying and photo-polymerizing the fullerene monomer solution according to an embodiment of the present invention.

[25]

Mode for the Invention

[26] The present invention relates to a manufacturing method of fullerene manifold having a characteristic of white photoemission, it can be divided into steps of making fullerene monomers into fullerene assembly by micro-spraying method, making fullerene manifolds by photo-polymerization reaction induced by irradiating UV laser to the fullerene assembly, and capturing the fullerene manifold.

[27] First of all, the step of making the fullerene assembly according to the present invention is to make fullerene solution by dissolving a fullerene monomer into toluene, benzene, CH Cl (Dichloromethane, Methylene Chloride / MC) and the like as a solvent. Next, the dissolved oxygen is removed by pouring Ar gas into the fullerene monomer dissolved solution. And, the fullerene solution free from the dissolved oxygen is sprayed into solution droplets of micrometer size in a vacuum by ultrasonic vibrator and the like. And then, the sprayed fullerene solution droplets is made to be evaporated in a vacuum.

[28] It is desirable to remove the dissolved oxygen from the fullerene solution, in order to eliminate a bad influence in the process of making fullerene assembly.

[29] If the sprayed fullerene solution droplets of several nanometer size are evaporated in a vacuum as stated above, the amount of the solution is decreased and concentrated as the fullerene dissolving solvent is evaporated, and the distances between fullerene monomers get closer in a condensation process of the solution. When fullerene monomers get closer to each other within a certain distance, fullerene monomers are combined to form a fullerene assembly by Van der Waals' force.

[30]

[31] As an embodiment of the present invention, fullerene powder of high purity over

99.995% that is easily purchasable in the market and manufactured by Buckey Co., Inc. is used as fullerene monomer, and toluene, benzene or MC(Methylene Chloride) of 99.99% purity is used as a solvent for dissolving the fullerene powder.

[32]

[33] And, fullerene solution with a concentration of 2.5x10 mol/L or more is made by dissolving the fullerene powder with solvent, the fullerene solution manufactured above is loaded in a vessel to be closed tightly, and the dissolved oxygen in the fullerene solution is removed by passing Ar gas. At this time, if the volume of fullerene solution is 500 ml, the dissolved oxygen is removed by passing Ar gas at least for 2 hours.

[34] From the fullerene solution free from dissolved oxygen, fullerene solution droplets of several micrometers sizes are generated by using ultrasonic vibrator or other spraying methods in a vacuum vessel below 1.0x10 Torr. At this time, in case that the volume of fullerene solution is about 500 ml, fullerene solution droplets of several nanometers sizes are generated by spraying fullerene solution for 4 hours in total, by the method of spraying 40 ml of solution into droplets per 15 - 20 minutes,

[35] Maintaining the vessel in a vacuum condition below 1.0x10 Torr is to induce natural evaporation of solvent in a vacuum. And, maintaining the vacuum condition below 1.0x10 Torr and removing the dissolved oxygen from fullerene solution is for the purpose of inducing natural evaporation of solvent in a vacuum to form fullerene and minimizing the influence of the oxygen molecules in air in the process of ir- radiating UV laser stated later to the fullerene assembly made in the above process. Generally, C fullerene is known as sensitive to oxygen molecules contained in a solution. Because if fullerene assembly or fullerene manifold is generated in the existence of oxygen, the problem is occurred that near infrared rays PL(Photo Luminescence) is detected at the energy range of 1268 nm in PL of solution due to the influence of the oxygen, it is desirable to remove dissolved oxygen in fullerene solution using a gas for removing the dissolved oxyen and minimize oxygen in the air during spraying process or UV laser irradiation process by making vacuum condition.

[36]

[37] Next, the fullerene solution droplets generated to be several nanometers sizes are left in a vacuum condition. At this time, the solvent are evaporated naturally from the solution droplets during the above process such that the solution droplets are condensed according to the rate of evaporation.

[38]

[39] The fullerene monomers in the solution droplets get closer to each other through the above condensation process. When the fullerene monomers get closer to each other within a certain distance, the fullerene monomers are combined with each other to form a fullerene assembly by Van der Waals' force.

[40]

[41] Next, a manufacturing method of fullerene manifolds with a charateristic of white photoemission using fullerene assembly manufactured by the micro-spraying method utilizes a method of manufacturing the fullerene manifolds through photo- polymerization reaction induced by irradiating UV laser on the fullerene assembly.

[42] That is, irradiating UV on the fullerene assembly induces a formation of covalence bonding by the photo-polymerization reaction between fulleren molecules and generates fullerene manifold. Because the fullerene manifolds are combined by covalence bonding, differently from fullerene manifolds having weak bonding by Van der Waals' forces, they cabn be maintained in a manifold state without dividing into each fulleren monomers even at room temperature.

[43] Also, the fullerene assembly made in the embodiment stated above is passed through quartz glass tube or pyrex glass tube to be irradiated by UV laser using UV lamp from outside of the glass tube. At this time, if the volume of solvent for manufacturing the fullerene assembly is 500 ml, the fullerene assembly with a characteristic of white photoemission is manufactured by the photo-polymerization reaction for 4 hours.

[44] Because the fullerene assemblies manufactured above are solution droplets of micrometers sizes like a mist, a step for capturing them to make liquid state is required.

[45] FIG. 1 to 5 show UV absorption spectrums measured after generating fullerene assembly by spraying 500 ml of fullerene solution having a diffent concentration of dissolved fullerene monomers respectively by the micro-spraying method and photo- polymerization reaction of the fullerene assembly for 4 hours. FIG 1 shows UV absorption spectrum measured after the photo-polymerization reaction in case the concentration of fullerene monomers is 1x10 mol/L. FIG. 2 shows another UV absorption spectrum in case the concentration of fullerene monomers is 5x10 mol/L, FIG. 3 shows that in case the concentration of fullerene monomers is 2.5x10 mol/L and FIG. 4 shows UV absorption spectrum in case the concentration of fullerene monomers is 2x10 mol/L.

[46] To measure whether the photo-polymerization occurred or not, UV absorption spectrums are measured after removing the solvent using a rotary decompression evaporator from the fullerene solution having passed through photo-polymerization reaction by irradiating UV laser, and dissolving the fullerene reactant gained above with toluene for GPC. At this time, a reason for re-dissolving the fullerern reactant with toluene for GPC is to apply directly the result of the reaction to the measurement using HPLC after measuring the UV absorption spectrum.

[47] Also, UV absorption spectrums are measured in the range of 200 ~ 700 nm. High peaks of UV absorption spectrum of fullerene molecules(monomers) are observed near 340 nm. The peaks are reduced in the range of 340 nm when fullerene assembly is generated through photo-polymerization reaction.

[48] Accordingly, as the results of UV absorption spectrums analysed in the graphs of

FIG 1 to 4, peaks in the range of 340 nm are decreased remarkably in the graphs of FIG. 2(5xlO^"6 mol/L) and FIG. 3(2.5xlO^"6 mol/L), and they mean that fullerene manifolds having characteristics different from those of fullerene monomers are manufactured. That is, the fullerene manifolds are synthesized by photo-polymerization reaction between molecules of fullerene assembly manufactured by the micro- spraying method.

[49] On the contrary, peaks appeared remarkably in the range of 340 nm in the graphs of

FIG. 1 and FIG. 4, and they are similar to the shape of UV absorption spectrum of fullerene monimers, and these mean that there are a lot of fullerene monomers not to be generated into fullerene manifolds since there were no photo-polymerization reactions by UV.

[50] As stated above, if a concentration of fullerene monomers dissolved in a solvent is over 2.5x10 mol/L when manufacturing fullerene manifold by micro spraying method, a great quantity of fullerene assembly can be made.

[51]

[52] Also, as another method of measuring whether fullerene manifolds are generated through photo-polymerization reaction from the fullerene assembly made by the micro- spraying method or not, the generation of fullerene manifold can be confirmed through a test measuring the molecular weight and magnitude, since molecular weight and magnitude of fullerene manifold is larger than those of fullerene monomer. In this regard, an analysis using HPLC is mainly used as a method for measuring molecular weight.

[53] HPLC system(produced by JASCO Co., Ltd.) using for HPLC measurement consists of a pump(PU-2086) enabling speed control in the range of lμm/min to 20.0 ml/min, a detector(UV-2075) enabling measurement in the range of 190 nm to 900 nm, an In-line degasser(DG-2080), and a column oven(CO-2065) enabling control of temperature by unit of 0.1 degree in the range of 10 ~ 15 degree. In the present invention, JAIGEL- IH(IH-F) and JAIGEL-3H(3H-F) are used among JAIGEL-H series(JAI Co., Ltd) as column such that material of larger molecular weight comes out first. In the test, the speed of pump is set to be 3 ml/min and the data measured in the detector are recorded in real time on PC using A/D converter(JASCO Co. LC-NetII box). Here, SmartChrom(KYA TECH Corporation) is used as a control program.

[54] After dissolving fullerene monomers in toluene for GPC and measuring sample which is moving with a speed of 3 ml/ min, fullerene is observed at 60 min as shown in FIG. 5, as a result.

[55] FIG. 6 shows the result of HPLC measurement of fullerene manifold solution through photo-polymerization reaction induced by irradiating UV on the solution of fullerene dissolved in toluene at the concentration of 2.5x10 M. As compared with FIG. 5, it can be found that the peak appearing at 60 min is that of fullerene monomers without photo-polymerization reaction by UV. Further, values of peaks at 52 min and the previous time are those of fullerene manifolds larger than fullerene monomers in molecular weight, considering that larger material in molecular weight is measured in advance due to the characteristic of the used column.

[56] As stated above, a fullerene manifold can be made by photo-polymerization reaction induced by irradiating UV laser on the fullerene assembly made by the micro- spraying method during the predetermined time, according to present invention. At this time, the manufactured fullerene manifold has a characteristic of white photoemission in the whole range of visible rays, and this characteristic results from 3-dimensional network of covalent bonds formed by photo-polymerization reaction in the fullerene assembly having CSC(Closed Shell Structure).

[57]

[58] While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in forms and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. The preferred embodiments should be considered in descriptive sense only and not for purposes of limitation. Therefore, the scope of the invention is defined not by the detailed description of the invention but by the appended claims, and all differences within the scope will be construed as being included in the present invention.

[59]

Industrial Applicability

[60] According to the present invention, 3-dimensional structured fullerene manifold which could not be obtained from the fullerene manifold manufactured with usual bulk material using light, pressure and doped metal can be manufactured in a scale of nanometer, and such fullerene manifold can be applied to a variety of display devices which require white photoemission characteristic.

[61]

[62]

Claims

[1] A method of manufacturing fullerene manifold comprising: generating fullerene solution by dissolving fullerene monomers in a single solvent; spraying the fullerene solution into solution droplets of micrometer size; and making fullerene assembly by natural evaporation of the droplets of the sprayed fullerene solution in a vacuum.

[2] The method of claim 1, wherein further comrising: inducing photo-polymerization reaction of fullerene assembly by irradiating UV laser to the made fullerene assembly; and capturing the fullerene manifold generated by photo-polymerization reaction into liquid state.

[3] The method of claim 1 or claim 2, wherein the single solvent is any one of benzene, toluene and CH Cl .

2 2

[4] The method of claim 1 or claim 2, wherein a concentration of the fullerene monomers dissolved in the single solvent is equal to or higher than 2.5x10 mol/

L. [5] The method of claim claim 2, wherein the vacuum condition is maintained equal to or lower than 1.0x10 Torr. [6] The method of claim 2, wherein further comprising: removing dissolved oxygen from the fullerene monomers dissolved solution. [7] The method of claim 5, wherein the material for removing the dissolved oxygen is Ar gas. [8] The method of claim 1, wherein further comprising: separating the solvent from the captured fullerene manifold solution using a rotary decompression evaporator.