• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.152-152
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• 2004

카본나노튜브(Carbon Nanotube)는 다른 물질과 구별되는 날카로움(Sharpness), 고세장비(High Aspect Ratio), 높은 기계적 강성(Stiffness), 고탄성(high Elasticity), 그리고 반도체(semi-conducting)와 도체(Metallic) 성질 때문에, 카본나노튜브는 많은 연구에 적용되고 있으며, 카본나노튜브가 부착된 AFM(Atomic Force Microscope) 팁을 이용한 AFM 측정은 CNT 응용에 있어서 매우 큰 효과를 내는 응용분야 중 하나이다. AEM 팁에 카본나노튜브를 붙이는 이전 연구는 대부분 화학증착법(Chemical Vapor Deposition)에 의해 이루어 졌으며, 매우 효과적인 방법이지만 고가의 장비와 고온의 챔버내에서 이루어진다는 문제점을 가지고 있다.(중략)

• 한국재료학회지
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• 제21권3호
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• pp.180-185
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• 2011

This study is aimed to increase the activity of cathodic catalysts for PEMFCs(Polymer Electrolyte Membrane Fuel Cells). we investigated the temperature effect of 20wt% Pt/C catalysts at five different temperatures. The catalysts were synthesized by using chemical reduction method. Before adding the formaldehyde as reducing agent, process was undergone for 2 hours at the room temperature (RT), $40^{\circ}C$, $60^{\circ}C$, $80^{\circ}C$ and $100^{\circ}C$, respectively. The performances of synthesize catalysts are compared. The electrochemical oxygen reduction reaction (ORR) was studied on 20wt% Pt/C catalysts by using a glassy carbon electrode through cyclic voltammetric curves (CV) in a 1M H2SO4 solution. The ORR specific activities of 20wt% Pt/C catalysts increased to give a relative ORR catalytic activity ordering of $80^{\circ}C$ > $100^{\circ}C$ > $60^{\circ}C$ > $40^{\circ}C$ > RT. Electrochemical active surface area (EAS) was calculated with cyclic voltammetry analysis. Prepared Pt/C (at $80^{\circ}C$, $100^{\circ}C$) catalysts has higher ESA than other catalysts. Physical characterization was made by using X-ray diffraction (XRD) and transmission electron microscope (TEM). The TEM images of the carbon supported platinum electrocatalysts ($80^{\circ}C$, $100^{\circ}C$) showed homogenous particle distribution with particle size of about 2~3.5 nm. We found that a higher reaction temperature resulted in more uniform particle distribution than lower reaction temperature and then the XRD results showed that the crystalline structure of the synthesized catalysts are seen FCC structure.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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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.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.97-105
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• 1998

The goal of this study is to investigate the potential application of triboelectrostatic separation process for removing unburned carbon from fly ash. The process utilizes the difference in electrical charging characteristics between the organic material (carbon) and the mineral matter (fly ash). In the present work, dry separation tests have been conducted on Samchunpo fly ash samples using a bench - scale analytic separator. The test variables studied include air rate, feed rate, electric field strength, particle size, charger material and length, etc. The best separation results were obtained at the air rate 501/min, feed rate 15 g/min and voltage 15 ㎸. The fly ash with carbon content below 1 % was obtained with over 65% recovery.

• Corrosion Science and Technology
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• 제15권1호
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• pp.1-5
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• 2016

Zinc ethyl silicate coatings containing multi walled carbon nanotubes (MWCNTs) were prepared, to which we added spherical and flake shaped zinc particles. The anti-corrosive effects of MWCNTs and zinc shapes on the zinc ethyl silicate coated carbon steel was examined, using electrochemical impedance spectroscopy and corrosion potential measurement. The results of EIS and corrosion potential measurement showed that the zinc ethyl silicate coated with flake shaped zinc particles and MWCNT showed lesser protection to corrosion. These outcomes were in agreement with previous results of corrosion potential and corrosion occurrence.

• 조명전기설비학회논문지
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• 제24권7호
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• pp.57-63
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• 2010

Photo-capacitor electrodes are attracting great attention because of their high capacitance and potential applications in electronic devices. Carbon capacitor, active carbon capacitor and its combination will be fabricated using a sandwich method as carbonaceous material on each type of storable electrode with $20{\times}15$[mm] cell size. Carbon/active carbon cell was fabricated using sol-gel process with $120[^{\circ}C]$ dry temperature in 2hour and using sintering process with $500[^{\circ}C]$ in 2hour. The effect of sintering temperature on carbon properties was also investigated with an X-ray diffraction technique to get the best sintering temperature. The detail of the fabrication process will be explained. Active carbon as carbonaceous material has a better capacitance in storable electrode with mean thickness $32[{\mu}m]$ and with particle size $1[{\mu}m]$ to $4.5[{\mu}m]$ in $20{\times}15$[mm] sample size of storable electrode.

• 전기화학회지
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• 제8권4호
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• pp.168-171
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• 2005

The electrochemical properties of $LiFePO_4$ as a cathode for Li-ion batteries were improved by incorporating conductive carbon into the $LiFePO_4$. X-ray diffraction analysis and SEM observations revealed that the carbon-coated $LiFePO_4$ consisted of fine single crystalline particles, which were smaller than the bare $LiFePO_4$. The electrochemical performance of the carbon-coated $LiFePO_4$ was tested under various conditions. The carbon-coated $LiFePO_4$ showed much better performance in terms of the discharge capacity and cycling stability than the bare $LiFePO_4$. The improved electrochemical performances were found to be attributed to the reduced particle size and enhanced electrical conductivity of the $LiFePO_4$ by the carbon.

• 공업화학
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• 제20권4호
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• pp.396-401
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• 2009

전기이중층 캐패시터의 성능향상을 위한 전극물질로서 resorcinol-formaldehyde수지를 탄소원으로 사용하여 meso-pore 비율 52~64%의 기공특성을 지니며 직경 $2{\sim}10{\mu}m$의 미세구형 활성탄을 제조하였다. 이 활성탄을 전기이중층에 적용한 결과, meso-pore구조의 미세구형활성탄은 전하전달저항의 저감 및 충방전율 수용능력 향상에 효과적인 영향을 나타내어 전기이중층 캐패시터의 성능향상을 위한 효과적인 전극물질이 될 수 있음을 확인할 수 있었다.

• Carbon letters
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• 제7권2호
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• pp.87-96
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• 2006

This paper describes the physical properties of filled Nylon6 composites resin with nano-sized carbon black particle and graphite nanofibers prepared by melt extrusion method. In improving adhesions between resin and fillers, the surface of the carbon filler materials were chemically modified by thermo-oxidative treatments and followed by treatments of silane coupling agent. Crystallization temperature and rate of crystallization increased with increases in filler concentration which would act as nuclei for crystallization. The silane treatments on the filler materials showed effect of reduction in crystallization temperature, possibly from enhancement in wetting property of the surface of the filler materials. Percolation transition phenomenon at which the volume resistivity was sharply decreased was observed above 9 wt% of carbon black and above 6 wt% of graphite nanofiber. The graphite nanofibers contributed to more effectively in an increase in electrical conductivity than carbon black did, on the other hand, the silane coupling agent negatively affected to the electrical conductivity due to the insulating property of the silane. Positive temperature coefficient (PTC) phenomenon, was observed as usual in other composites, that is, temperature increase results conductivity increase. The dispersity of the fillers were excellently approached by melt extrusion of co-rotational twin screw type and it could be illustrated by X-ray diffraction and SEM.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.761-764
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• 2009

The thermocatalytic decomposition of methane is an environmentally attractive approach to $CO_2$-free production of hydrogen. The fluidized bed was proposed for the continuous withdraw of product carbon from the reactor. The usage of carbon black was reported as stable catalyst for decomposition of methane. Therfore, carbon black (DCC-N330) is used as catalyst. A fluidized bed reactor made of quartz with 0.055 m I.D. and 1.0 m in height was selected for the thermo-catalytic decomposition. The porpane-containg methnae decomposition reaction was operated at the temperature range of 850-900 $^{\circ}C$ methane gas velocity of 1.0 $U_{mf}$ and the operating pressure of 1.0 atm. In this work, propane was added as reactant to make methane conversion higher. Therefore we compared with methane conversion and pre-experiment methane conversion that using only methane as reactant. The carbon black, after experiment, was measured in particle size and surface area and analyzed surface of the carbon black by TEM.