• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.201-202
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• 2003

We developed a novel growth method of aligned carbon nanotubes. Aligned carbon nanotubes are grown on a metal catalyst on a glass substrate using biased Helicon plasma chemical vapor deposition (HPECVD) of $CH_4/H_2$ gases from 400 C to 500 C. The Helicon plasma source is one of the high-density plasma sources and is promising for low temperature carbon deposition. A Ni film was used as a catalyst to reduce the activation energy of the nanotubes' growth. The carbon nanotubes were deposited on the nickel catalysis layer selectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.263-263
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• 2010

High temperature annealing is required to synthesize graphene using CVD. When thin metal catalyst is used for the synthesis, the high temperature pre-annealing makes the thin catalyst highly agglomerated. We investigated the agglomeration effect on the shape of the synthesized graphene. It is found that high temperature annealing makes randomly distributed many hole or blister on metal catalyst, and the synthesized graphene features floral pattern around the hole. The floral patterns of graphene turned out to be multi-layers and higher D peaks in raman spectrum.

• Carbon letters
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• 제6권2호
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• pp.79-85
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• 2005

The work reported in this paper relates to preparation and characterization of carbon nanomaterials by CVD method on different substrates by decomposition of certain hydrocarbons at 550-$800^{\circ}C$ using a horizontal quartz tube reactor. Monometallic and bimetallic catalyst system of iron and nickel were used for the preparation of different carbon nanomaterials. The influence of various parameters such as substrate/catalyst preparation parameters, the nature of substrate, catalyst concentration, reaction time and temperature on the growth, yield and alignment of carbon nanotubes has been studied. The characterization of carbon nanomaterials has been carried out using SEM, TEM and TGA. The carbon nanomaterials developed were vertically aligned on a large area of flat quartz substrate.

• 한국재료학회지
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• 제11권8호
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• pp.703-707
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• 2001

크롬의 첨가에 따른 Raney 니켈의 특성을 파악하여 우수한 성능을 나타낼 수 있는 알칼리형 연료전지용 수소극의 촉매를 제조하였다. 또한 제조된 촉매를 이용, 실제 전극으로 제작하여 전류밀도를 측정한 뒤 최적의 전극재료의 제조조건을 확립하였다. 먼저 Ni-Al합금 제조시 크롬의 첨가량을 달리하여 Raney 니켈을 제조한 뒤 이를 이용하여 수소극을 제작, 전기화학적 특성을 고찰한 결과 크롬 첨가량이 증가함에 따라 mass activity도 증가하여 크롬 첨가량이 1 wt% 인 경우 최고 3.688 A/g을 나타내었다. 전기화학적 측정시 half cell의 운전온도는 8$0^{\circ}C$이었으며 전해질은 6N KOH이었다. Raney 니켈 촉매의 입자크기와 비표면 적을 조사한 결과 크롬의 첨가량이 증가함에 따라 Raney 니켈 촉매의 입자크기는 12.11 $\mu\textrm{m}$에서 크롬의 첨가량이 1.25 wt%인 경우 11.07 $\mu\textrm{m}$로 감소하였고 비표면적은 0.653 $\m^2$/g에서 0.685 $\m^2$로 중가함을 알 수 있었다. 평균입자 크기가 커짐에 따라 잔존 알루미늄의 함량은 증가함을 알 수 있었다.

• 한국수소및신에너지학회논문집
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• 제14권1호
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• pp.69-80
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• 2003

Nickel catalyst has been used for natural gas reforming with carbon dioxide, In this study, catalyst support used was HY zeolite. The optimum loading of Ni in the catalysts was 13 wt%. The effect of promoters, such as Mg, Mn, and K, was also studied. The addition of promoters to Ni catalyst improved the stability of catalysts and carbon deposition on Ni catalyst was suppressed. The reforming reactivity of promoter-added Ni catalyst was higher than that of Ni catalyst without any promoters. SEM, XRD, BET, TGA and FTIR tests were tried to characterize the catalyst structure before and after reaction.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2431-2437
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• 2014

In this study, Ni, Ni-Cu and Ni/Cu catalysts were deposited onto C-fiber textiles via the electrophoretic deposition method, and the growth characteristics of carbon nanofibers on the deposited catalyst/C-fiber textiles were investigated. The catalyst deposition onto C-fiber textiles was accomplished by immersing the C-fiber textiles into Ni or Ni-Cu mixed solutions, producing the substrate by post-deposition of Ni onto C-fiber textiles with pre-deposited Cu, and passing it through a gas mixture of $N_2$, $H_2$ and $C_2H_4$ at $700^{\circ}C$ to synthesize carbon nanofibers. For analysis of the characteristics of the synthesized carbon nanofibers and the deposition pattern of catalysts, SEM, EDS, BET, XRD, Raman and XPS analysis were conducted. It was found that the amount of catalyst deposited and the ratio of Ni deposition in the Ni-Cu mixed solution increased with an increasing voltage for electrophoretic deposition. In the case of post-deposition of Ni catalyst onto substrates with pre-deposited Cu, both bimetallic catalyst and carbon nanofibers with a high level of crystallizability were produced. Carbon nanofibers yielded with the catalyst prepared in Ni and Ni-Cu mixed solutions showed a Y-shaped morphology.

• 폴리머
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• 제29권2호
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• pp.156-160
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• 2005

Octamethylcyclotetrasiloxane$(D_4)$과 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane$(D_3^{Me,Ph)$을 1,1,3,3-tetramethyl-1,3-divinyldisiloxane(MVS)과 평형중합시켜 실리콘의 Si원자에 dimethyl 및 methylphenyl기가 도입된 $\alpha,\omega-vinyl$ poly(dimethyl-methylphenyl) siloxane prepolymer(VPMPS)를 제조하였으며, 또한 $D_4$와 1,3,5-trimethylcyclotrisiloxane$(D_3^:Me,H})$을 1,1,3,3-tetramethyldisiloxane(MS)와 평형중합시켜 Si원자에 dimethyl 및 methylhydrogen기가 도입된 $\alpha,\omega-hydrogen$ poly (dimethyl-methyl) siloxane prepolymer(HPDMS)를 제조하였다. Poly(acrylic acid)(PAA)을 chelating agent로 하여 nickel(II) nitrate와 iron(III) nitrate를 솔-젤 방법으로 PAA 금속염을 제조하고 이틀을 소결시켜 nickel ferrite 나노 입자를 제조하였다. 제조한 nickel ferrite는 XRD 패턴으로 확인하고 입자의 크기를 TEM으로 측정하였다 1,3-Divinyltetramethyldisilazane(VMS)으로 표면처리한 나노 실리카, nickel ferrite, VPMPS, HPDMS 및 촉매를 고속 교반기에 가하고 $130^{\circ}C$에서 컴파운딩하여 poly(organosiloxane) rubber nanocomposites를 제조하였다. Nickel ferrite 함유한 nanocomposite, POX-30과 POX-50을 각각 제조하였으며 이들의 기계적 및 열전도 특성 그리고 체적 저항을 측정하였다.

• 공업화학
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• 제24권4호
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• pp.375-381
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• 2013

상업용 니켈 촉매를 사용하여 메탄과 천연가스의 수증기 개질 반응을 각각 수행하였다. 수증기 개질 반응의 변수는 반응 온도와 반응물의 분압이었다. Kinetic data로부터 Power law rate model과 Langmuir-Hinshelwood model의 매개변수를 구하였다. 순수한 메탄을 수증기 개질 반응 실험의 원료로 사용한 경우에는 Langmuir-Hinshelwood model 식은 물론이고 Power law rate model을 사용하여 반응 속도를 적절하게 표현할 수 있었다. 그러나 천연가스 중의 메탄의 수증기개질 반응 속도를 표현하는데 있어서는 Power law rate model보다 Langmuir-Hinshelwood model이 훨씬 더 적합한 것을 확인하였다. 이러한 거동은 천연가스 중에 포함되어있는 메탄, 에탄, 프로판 및 부탄이 동일한 촉매 활성점에 경쟁적으로 흡착하기 때문으로 해석할 수 있었다.

• 자원리싸이클링
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• 제14권4호
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• pp.17-21
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• 2005

망간단괴 용융환원 시 철과 니켈을 주로 함유하고 있는 Ni-Cd 폐전지와 코발트 등을 함유한 석유화학 폐촉매를 대상으로 첨가 원료로서의 사용 가능성을 검토하였다. Ni-Cd 폐전지의 경우 망간단괴와의 첨가비에 관계없이 $5\%$ 코크스 첨가 시, 주회수 대상 금속인 니켈을 전량 합금상으로 회수할 수 있었다. 한편 폐촉매의 경우 폐촉매의 첨가비가 증가할수록 많은 환원제가 필요한데 이는 폐촉매 중의 코발트가 산화물 형태로 존재하여 이를 환원하기 위한 환원제가 필요하기 때문이다. 본 방법은 금속계 폐자원을 처리하고 동시에 유가금속을 회수할 수 있는 방법으로 향후 망간단괴 개발의 상용화 시 경제성을 증대시키고 폐자원의 재활용에 기여 할 것이다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.247-250
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• 2008

Biomass gasification is a promising technology for producing a fuel gas which is useful for power generation systems. In biomass gasification processes, tar formation often causes some problems such as pipeline plugging. Thus, proper tar treatment is necessary. So far, nickel (Ni)-based catalysts have been intensively studied for the catalytic tar removal. However, the deactivation of Ni-based catalysts takes place because of coke deposition and sintering of Ni metal particles. To overcome these problems, we have been using ruthenium (Ru)-based catalyst for tar removal. It is reported by Okada et al., that a Ru/$Al_2O_3$ catalyst is very effective for preventing the carbon deposition during the steam reforming of hydrocarbons. Also, this catalyst is more active than the Ni-based catalyst at a low steam to carbon ratio (S/C). Benzene was used for the tar model compound because it is the main constituent of biomass tar and also because it represents a stable aromatic structure apparent in tar formed in biomass gasification processes. The steam reforming process transforms hydrocarbons into gaseous mixtures constituted of carbon dioxide ($CO_2$), carbon monoxide (CO), methane ($CH_4$) and hydrogen ($H_2$).