• Carbon letters
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• v.27
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• pp.12-17
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• 2018

We fabricated a Li-S battery with post-treated carbon nanotube (CNT) films which offered better support for sulfur, and investigated the effect of the surface properties and pore structure of the post-treated CNT films on Li-S battery performance. Post-treatments, i.e., acid treatment, unzip process and cetyltrimethylammonium bromide (CTAB) treatment, effectively modified the surface properties and pore structure of the CNT film. The modified pore structure impacted the ability of the CNT films to accommodate the catholyte, resulting in an increase in initial discharge capacity.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.1
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• pp.42-46
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• 2006

This paper presents a method for deposition an individual carbon nanotube (CNT). The alignment of a single CNT is very useful to perform studies related to applications in FET (Field Emitted Transistor), SET (Single Electron Transistor) and to make chemical sensor as well as bio sensors. In this study, we developed the deposition method of a CNT individualized in a solution. Using the electrokinetic method, we found the optimum conditions to assemble the nanotube and discussed about plausible explanation for the assembling mechanism. These results will be available to use for making the CNT sensor device.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.6
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• pp.22-27
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• 2004

특성에 대한 많은 연구가 진행되었고, 새로운 나노 소자로서의 가능성을 보여왔다. CNT의 전기적 성질은 직경과 chirality 의 함수로서 금속 혹은 반도체 성질을 주기적으로 가지며, 이론적 연구에 의하면 단일구역의 CNT 는 1/3 이 금속성, 나머지는 밴드갭이 수 ㎷ 로 아주 작고, 나노튜브의 직경에 반비례하는 반도체 성질을 나타낸다.(중략)

• Journal of the Semiconductor & Display Technology
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• v.6 no.1 s.18
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• pp.27-30
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• 2007

The gigahertz oscillator behavior of double-walled boron-nitride nanotube (BNNT) was investigated by using classical molecular dynamics simulations. The BNNT oscillator characteristics were compared to carbon-nanotube (CNT) and hybrid-C@BNNT oscillators. The results show that the BNNT oscillators are higher than the van der Waals force of the CNT oscillator. Since the frictional effects of BNNT oscillators are higher than that of a CNT oscillator, the damping factors of BNNT and hybrid oscillators are higher than that of a CNT oscillator.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.9
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• pp.813-819
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• 2011

This paper predicted nonlinear dynamic responses of a cantilevered carbon nanotube(CNT) resonator incorporating the electrostatic forces and van der Waals interactions between the CNT cantilever and ground plane. The structural model of CNT includes geometric and inertial nonlinearities to investigate various phenomena of nonlinear responses of the CNT due to the electrostatic excitation. In order to solve this problem, we used Galerkin's approximation and the numerical integration techniques. As a result, the CNT nano-resonator shows the softening effect through saddle-node bifurcation near primary resonance frequency with increasing the applied AC and DC voltages. Also we can predict nonlinear secondary resonances such as superharmonic and subharmonic resonances. The superharmonic resonance of the nano-resonator is influenced by applied AC voltage. The period-doubling bifurcation leads to the subharmonic resonance which occurs when the nano-resonator is actuated by electrostatic forces as parametric excitation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.11
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• pp.943-947
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• 2007

The effect of hydrogen and oxygen plasma treatments on the structural properties of carbon nanotube(CNT) has been systematically investigated. As the plasma power was increased, nano particles were appeared at the surface of CNTs. At high plasma power(300 Watt), the structure of CNT was changed from nanotube type to nano particles. However, in case of hydrogen plasma treatment, there was no change in microstructure of CNT. From the Raman analysis, the crystallinity of CNT was deteriorated by the plasma treatment, regardless of gas types.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.1
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• pp.45-49
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• 2020

In this paper, we prepared miniature fuse fabricated with carbon nanotube (CNT) fiber for the use of low rated current under 1 A and high speed operation under 4ms. CNT fuses were fabricated in the form of universal modular fuse (UMF) with different diameter of CNT fibers defined by multiplying the CNT threads. Electrical properties of the CNT fuses were measured such as resistance, rated current, and operation time with current. Resistance of the CNT fuse decreased and rated current increased with the diameter of the CNT fuses, respectively. Consequently, the operation time with current increased with the diameter of the CNT fuses. The CNT fuses fabricated in this work had broad range of low rated current from 0.05 to 1.25 A by multiplying the CNT threads. Operation time was measured about 3.6ms which was applicable to the UMF.

• International Journal of Precision Engineering and Manufacturing
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• v.6 no.2
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• pp.46-49
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• 2005

Recently, many research results have been reported about nano-tip using carbon nanotube because of its better sensing ability compared to a conventional silicon tip. However, it is very difficult to identify the carbon nanotube having proper length for nano-tip and to attach it on a conventional tip. In this paper, a new method is proposed to make a nano-tip and to control its length. The electrochemical etching method was used to control the length by cutting the carbon nanotube of arbitrary length and it was possible to monitor the process through current measurement. The etched volume of carbon nanotube was determined by the amount of applied charge. The carbon nanotube was successfully cut and could be used in the nanogripper.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.50-55
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• 2008

Carbon Nanotube (CNT) films were deposited with varying deposition temperature by RF plasma CVD on Fe catalysts deposited onto $SiO_2$ films grown thermally on the silicon wafer using $C_2H_2$ and $H_2$ gases. The Fe catalysts on silicon oxide film were made by RF magnetron sputtering. The grounded grid mesh cover on the substrate holder was used for depositing CNT thin films with high purity. The surface morphologies and chemical structure of deposited CNT films were characterized using SEM, Raman, XPS and TEM. It was observed that deposited CNTs films were carbon fiber type having Bamboo-like multiwall structure and CNT film grown at $600^{\circ}C$ was more dense than that at $550^{\circ}C$, but become less dense at $650^{\circ}C$.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.986-990
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• 2004

In this paper, we propose a method to estimate the actuating voltage of the nanotweezer made by manual assembly using carbon nanotube. The nanotweezer is composed of two CNT arms that are made by the multiwalled carbon nanotube and tungsten tip. Since the each CNT arm has the macro actuator, the nanotweezer can manipulate a large particle and it is possible to close and open the CNT arm repeatedly. The closing voltage, i.e., actuating voltage is calculated using the capacitance between the carbon nanotubes in CNT arm. We demonstrate the actuation of the nanotweezer using the voltage calculated with the electrostatic force.