• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1233-1234
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• 2006

A simple new method to fabricate transparent carbon nanotube field emission devices was developed. The highly graphitized single wall carbon nanotubes were attached on Sn/ITO glass by arc discharge method. Post heat treatments below the deformation temperature of soda-lime glass guaranteed a good mechanical adhesion and electrical contact of the nanotubes. The Sn layer was oxidized below $400^{\circ}C$ and became transparent. As increasing the oxidation temperatures, the emission properties became stable and life time of emitter has been increased.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.611-611
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• 2013

In this study, iron oxide nanoclusters layer (Nc) was prepared onto functionalized silicon substrate by wet method. The amine-terminated SAM fabricated on silicon substrate (APTMS/Si) was carried out by UV-treatment and immersed into the FeCl3/HCl aqueous solution. Then, Nc were immobilized onto oxidized SAM silicon substrate (SAMs/Si) through electrostatic interaction between cationic Nc and anionic SAMs/Si. This catalytic layer (Nc/SAMs/Si) was used to grow carbon nanotubes (CNTs). The characterization results clearly show that the well-graphitized CNTs were synthesized by using functionalized silicon substrate as a template having appropriate density of catalyst. These consequences show that SAM containing template is important to achieve the effective layer of catalyst to synthesize CNTs.

• Journal of Electrochemical Science and Technology
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• 제1권2호
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• pp.92-96
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• 2010

A new synthesis method for the preparation of Pt electrocatalysts on carbon nanofibers (CNFs) is reported. In this method, Pt electrocatalysts are loaded onto 2-naphthalenethiol (NT) functionalized CNFs. The noncovalent functionalization of CNFs by NT is the effective way for better distribution of Pt particles and higher electrocatalytic activity in polymer electrolyte membrane fuel cells. It was found that the presence of NT acts as a poison to catalysts. Therefore, it is necessary to remove NT through the heat treatment at $400^{\circ}C$.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.117-123
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• 1996

Cabon fiber of general purpose was prepared from coal tar pitch modified with 10% benzoquinine(BQ) at 380C for 3 hours. Such a modified pitch raised the softening of the pitch from 85C to 271C at the yield of 40%. The modified pitch was spun smoothly at a rate of 480m/min into a fiber of 20um diameter. The fiber was stabilized stepwise at 236C (5C/min) and 312C (1C/min) for 3 hours each. Both carbonized and graphitized fibers exhibited tensile strength of 570MPa which appears large enough as a precursor for active carbon fiber. The activated carbon fiber prepared exhibited relatively high surface area of 2062m2/g at 76% burn-off and rather narrow distribution pore size of 20A.

• 한국세라믹학회지
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• 제30권7호
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• pp.557-562
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• 1993

Following conclusions are made from the detalied research on the relation between the phase change of the petroleum raw cokes after ball milling and the preheat treatment temperature. The petroleum raw cokes species are preheated in the temperature range of 350~45$0^{\circ}C$. At the preheat treatment temperature of 40$0^{\circ}C$ the particles of petroleum raw cokes from ball milling become spheically shape with the almost uniform particle size distribution of 1~5${\mu}{\textrm}{m}$. At the same temperature, they became low-graphitized with the d0.02 X-ray diffraction index of 3.41$\AA$. The carbon material made from the petroleum raw cokes at 40$0^{\circ}C$ turned out to have the good modulus of rupture about 600kg/$\textrm{cm}^2$, with the bulk density around 1.8g/㎤ and the appearent porosity around 8%.

• Carbon letters
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• 제5권3호
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• pp.118-126
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• 2004

MCMB (Mesocarbon microbeads) is a kind of anode material for lithium-ion secondary battery. MCMB charge/discharge cycle stability is one of the important criterion at lithium-ion battery operation. In this study, the cycling stability of a lithium-ion secondary battery has been examined. MCMB was made by the direct solvent extraction method. After the MCMB was carbonized and graphitized, the measurement of charge/discharge capacity and efficiency were carried out. In the result, discharge capacity of MCMB in the initial cycle was above 290.0 mAh/g. After the second cycle, efficiency of charge/discharge MCMB was about 98%. These results were similar to the commercial MCMB product.

• 공업화학
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• 제18권6호
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• pp.580-586
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• 2007

본 연구에서는, 프리폼 구조가 다른 4방향성 탄소/탄소 복합재를 제조하고, 그들의 열물리적 특성을 연구하였다. 탄소섬유 프리폼은 네 가지의 다른 간격의 섬유다발로 직조하였다. 직조한 프리폼들은 가압함침 및 탄화 공정을 통해 고밀도화하였다. 고밀도화된 복합재는 $2300^{\circ}C$에서 흑연화하였다. 이 복합재의 미세구조는 주사전자현미경을 통해 관찰하였다. 프리폼의 구조가 탄소/탄소 복합재의 열물리적 특성에 미치는 영향을 알아보기 위해 연구하였다. 그리고, 열전달 및 열팽창 거동은 섬유의 보강방향과 프리폼의 단위 격자에 따른 여러 인자들로 연구 검토하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.231-234
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• 2000

Vertically aligned carbon nanotubes were synthesized on Ni-coated Si substrates using microwave plasma-enhanced chemical vapor deposition. The grain size of Ni thin films was varied with the RF power density during the RF magnetron sputtering process. It was found that the diameter, growth rate, and density of carbon nanotubes could be controlled systematically by the grain size of Ni thin films. With decreasing the grain size of Ni thin films, the diameter of the nanotubes decreased, whereas the growth rate and density increased. High-resolution transmission electron microscope images clearly demonstrated synthesized nanotubes to be multiwalled. The number of graphitized wall decreased with decreasing the diameter. Field emission properties will be further presented.

• 한국전기전자재료학회논문지
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• 제19권8호
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• pp.701-706
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• 2006

In addition to its similarity to genuine diamond film, diamond-like carbon (DLC) film has many advantages, including its wide band gap and variable refractive index. In this study, DLC films were prepared by the RF PECVD (Plasma Enhanced Chemical Vapor Deposition) method on silicon substrates using methane $(CH_4)$ and hydrogen $(H_2)$ gas. We examined the effects of the post annealing temperature on the structural variation of the DLC films. The films were annealed at temperatures ranging from 300 to $900^{\circ}C$ in steps of $200^{\circ}C$ using RTA equipment in nitrogen ambient. The thickness of the film and interface between film and substrate were observed by surface profiler, field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), respectively. Raman and X-ray photoelectron spectroscopy (XPS) analysis showed that DLC films were graphitized ($I_D/I_G$, G-peak position and $sp^2/sp^3$ increased) ratio at higher annealing temperature. The variation of surface as a function of annealing treatment was verified by a AFM and contact angle method.

• Carbon letters
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• 제21권
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• pp.33-50
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• 2017

In this study, Fe-Ni bimetallic catalyst supported on kaolin is prepared by a wet impregnation method. The effects of mass of kaolin support, pre-calcination time, pre-calcination temperature and stirring speed on catalyst yields are examined. Then, the optimal supported Fe-Ni catalyst is utilised to produce multi-walled carbon nanotubes (MWCNTs) using catalytic chemical vapour deposition (CCVD) method. The catalysts and MWCNTs prepared using the optimal conditions are characterized using high resolution transmission electron microscope (HRTEM), high-resolution scanning electron microscope (HRSEM), electron diffraction spectrometer (EDS), selected area electron diffraction (SAED), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET), and X-ray diffraction (XRD). The XRD/EDS patterns of the prepared catalyst confirm the formation of a purely crystalline ternary oxide ($NiFe_2O_4$). The statistical analysis of the variance demonstrates that the combined effects of the reaction temperature and acetylene flow rate predominantly influenced the MWCNT yield. The $N_2$ adsorption (BET) and TGA analyses reveal high surface areas and thermally stable MWCNTs. The HRTEM/HRSEM micrographs confirm the formation of tangled MWCNTs with a particle size of less than 62 nm. The XRD patterns of the MWCNTs reveal the formation of a typical graphitized carbon. This study establishes the production of MWCNTs from a bi-metallic catalyst supported on kaolin.