• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.897-899
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• 2007

Transparent electrodes for a flexible display based on the liquid crystal (LC) were formed by carbon nanotubes (CNTs) on polyethylene terephthalate (PET) substrates. The thin multi wall carbon nanotubes (t-MWNTs) networks for electrodes were obtained by filtration- transfer method from welldispersed CNTs solution.

• Carbon letters
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• v.10 no.1
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• pp.19-22
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• 2009

In this work, the hydrogen storage behaviors of carbon nanotubes (CNTs)/metal-organic frameworks-5 (MOF-5) hybrid composites (CNTs/MOF-5) were studied. Hydrothermal synthesis of MOF-5 was conducted by conventional convection heating using 1-methyl-2-pyrrolidone (NMP) as a solvent. Morphological characteristics and average size of the CNTs/MOF-5 were also obtained using a scanning electron microscopy (SEM). The pore structure and specific surface area of the CNTs/MOF-5 were analyzed by N2/77 K adsorption isotherms. The capacity of hydrogen storage of the CNTs/MOF-5 was investigated at 298 K/100 bar. As a result, the CNTs/MOF-5 had crystalline structures which were formed by hybrid synthesis process. It was noted that the CNTs/MOF-5 can be potentially encouraging materials for hydrogen adsorption and storage applications at room temperature.

• Journal of Electrical Engineering and Technology
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• v.6 no.5
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• pp.688-692
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• 2011

Carbon nanotubes (CNTs) are vertically grown inside high-aspect-ratio vertical pores of anodized aluminum oxide. A CNT catalyst layer is introduced by atomic layer deposition to the bottom of the pores, after which the CNTs are successfully grown from the layer using chemical vapor deposition. The CNTs formed a complete vertical conductive path. The conductivity of the CNT-vertical path is also measured and discussed. The present atomic layer deposition-incorporated catalyst deposition is predicted to enable the integration of CNTs with various challenging configurations, including high-aspect-ratio vertical channels or vertical interconnects.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.10
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• pp.930-934
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• 2006

This paper reports a change of carbon nanotubes(CNTs) properties by post-treatment process after growth of CNTs. CNTs were treated by thermal method and solution method, and then investigated in detail using field emission scanning electron microscopy(FE-SEM), high resolution transmission scanning electron microscopy(HR-TEM), RAMAN spectroscopy, and Fourier Transform Infrared Spectrometer (FT-IR). FT-IR spectra showed that the amount of hydroxyl generated on surface of CNTs were changed with post-treatment condition. FE-SEM and TEM images were shown CNTs diameter and density variations were dependent with their treatment conditions. RAMAN spectroscopy was shown that carbon nanotubes structure vary with treatment conditions.

• Carbon letters
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• v.14 no.1
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• pp.1-13
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• 2013

Carbon nanotubes (CNTs) are increasingly attracting scientific and industrial interest because of their outstanding characteristics, such as a high Young's modulus and tensile strength, low density, and excellent electrical and thermal properties. The incorporation of CNTs into polymer matrices greatly improves the electrical, thermal, and mechanical properties of the materials. Surface modification of CNTs can improve their processibility and dispersion within the composites. This paper aims to review the surface modification of CNTs, processing technologies, and mechanical and electrical properties of CNT-based epoxy composites.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.3
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• pp.245-249
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• 2011

Carbon nanotubes (CNTs) have been significantly used for the field emitters for display applications. However, the lifetime of CNT emitters which are formed by screen printing technique is not guaranteed yet, because the constituents in CNT paste affect the lifetime of CNTs. The CNT pastes for screen printing are normally composed of organic vehicles (nitro cellulose, ethyl cellulose, etc) and additives (glass frits, indium tin oxide (ITO), etc) with CNTs. In this study, the effects of constituents in CNT pastes on the lifetime and emission characteristics of CNTs were investigated by thermal and electrical analysis. Use of glass frits worsened the lifetime and electron emission of CNTs. However, an addition of ITO to CNT paste rather improved the lifetime of CNTs. Degradation of CNTs was small when nitro cellulose was used in CNT paste as an organic vehicle.

• Korean Chemical Engineering Research
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• v.55 no.6
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• pp.854-860
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• 2017

PSf/D2EHPA/CNTs beads were prepared by immobilizing extractant di-(2-ethylhexyl)- phosphoric acid (D2EHPA) and adsorbent carbon nanotubes (CNTs) on polysulfone (PSf), and the adsorption characteristics of Sr(II) on the beads were studied. The morphological characteristics of the prepared PSf/D2EHPA/CNTs beads were observed by scanning electron microscopy (SEM), thermo gravimetric analysis (TGA), and Fourier transform infrared spectrometer (FTIR). The equilibrium time for the removal of Sr(II) by PSf/D2EHPA/CNTs beads was 60 min. The experimental kinetic data followed pseudo-second-order model more than pseudo-first-order kinetics model. The maximum removal capacity of Sr(II) obtained from Langmuir isotherm was 4.75 mg/g. The removal efficiencies of Sr (II) by PSf/D2EHPA/CNTs beads were improved 2.5 times by adding the adsorbent CNTs more than by using only the extractant D2EHPA.

• Bulletin of the Korean Chemical Society
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• v.25 no.10
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• pp.1521-1524
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• 2004

The effect of $H_2$ gas on the carbon nanotubes (CNTs) synthesis with CO-$H_2$ gas mixture was investigated using mass measurements and scanning electron microscopy (SEM). The maximum weight and yield of the synthesized carbon were obtained when the mixture ratio of $H_2$: CO was 3 : 7 and 9 : 1, respectively. In case of 100% carbon monoxide (CO) without hydrogen ($H_2$) addition, the weight of carbon increased, but CNTs were not observed. The CNTs began to be made when the contents of $H_2$ reaches at least 10%, their structures became more distinct with an increase of $H_2$ addition, and then the shapes of CNTs were more thin and straight. When the contents of $H_2$ was 80% ($H_2$ : CO = 8 : 2), the shapes and growth of CNTs showed an optimal condition. On the other hand, when the contents of $H_2$ was higher than the critical value, the shapes of CNTs became worse due to transition into inactive surface of catalyst. It was considered that the inactive surface of catalyst resulted from decrease of carbon (C) and $H_2$ concentration by facilitation of methane ($CH_4$) gasification reaction (C + 2$H_2$ ${\rightarrow}$ $CH_4$) between C and $H_2$ gases. It was also found that H2 addition had an influence considerably on the shape and structure of CNTs.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.666-669
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• 2002

Vertically aligned carbon nanotubes (CNTs) have been produced using various type of plasma enhanced chemical vapor deposition (PECVD). Catalysts such as Ni, Co, and Fe are used for growth of CNTs. To explain the effect of catalysts on the growth characteristics of CNTs, carbon species of $C_2H_2$ was observed in different catalysts using optical emission spectroscopy (OES) with theoretical calculation on the surface reaction in different catalysts.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.7
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• pp.49-54
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• 2010

The cryogenic ball milling was performed on carbon nanotubes (CNTs) at an extremely low temperature to increase the dispersion of CNTs. The effects of milling speed and time on the deagglomeration and structural changes of CNTs were studied. FESEM was used to analyze the dispersion and the change of particle size before and after milling process. Transmission electron microscopic (TEM) analysis was also investigated the effect of cryogenic ball milling on the morphological characteristics of CNTs. The structural changes by the cryogenic ball milling process were further confirmed by x-ray diffraction (XRD) and Raman spectroscopic analysis. The results showed that the agglomeration of CNTs was significantly reduced and amorphous structure was observed at high milling speed. However, the milling time has no great effect on the dispersion property and structural change of CNTs compared with milling speed.