• 제목/요약/키워드: fullerene

검색결과 178건 처리시간 0.031초

탄소나노튜브 분말의 에너지저장 이용 (Application of Carbon Nanotube Powders to Energy Storage)

  • 안중호
    • 한국분말재료학회지
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    • 제11권4호
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    • pp.279-287
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    • 2004
  • 탄소재료는 결정구조에 따라 카본블랙(carbon black), 그라파이트(graphite), 탄소섬유(carbon fiber) 등 다양한 형태가 있으며 그 응용 또한 광범위하다. 이는 탄소재료가 화학적으로 매우 안정하고, 열 및 전기전도성이 우수하며, 기계적인 특성면에서도 고강도, 고탄성율을 가지고 있어서 구조적으로 안정하기 때문이다. 특히 $C_{60}$(fullerene)와 탄소나노튜브(carbon naotube : CNT)등 근래 새로이 발견된 탄소물질들$^{1.2)}$ 은 그 독특한 결정구조와 성질로 인해 다양한 분야의 응용이 예상된다.

고분자 층이 도입된 네마틱 액정 시스템의 광굴절 효과 기작 (Mechanism of Photorefractive Effect in Polymer Layered Nematic Liquid Crystal Systems)

  • Mun Jun-Ho;Yun Chun-Seop;Kim Hyeon-Uk;Choe Su-An;Kim Jong-Deuk
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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    • pp.206-207
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    • 2001
  • The photorefractive (PR) effect in liquid crystals sandwiched between photoconductive polymer layers was first studied by Ono et al. They reported that the PR effect vanished at steady state If there were not insulating layers because no charge trapping occurred in the photoconductive poly(N-vinylcarbazole) (PVK) layers. However we observed a significant PR effect in the polymer layered liquid crystal (PLLC) system where a liquid crystal layer doped with fullerene is sandwiched between two photoconductive PVK layers. (omitted)

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Kinetics and Catalytic Activity of Carbon-Nickel Nanocomposites in the Reduction of 4-Nitrophenol

  • Li, Jiulong;Ko, Jeong Won;Ko, Weon Bae
    • Elastomers and Composites
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    • 제50권3호
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    • pp.217-222
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    • 2015
  • Carbon-nickel nanocomposites were prepared by the reaction of fullerene ($C_{60}$) and nickel hydroxide in an electric furnace at $700^{\circ}C$ for 2 h. The hybrid carbon-nickel nanocomposites were characterized by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. The kinetics and catalytic activity of the carbon-nickel nanocomposites in the reduction of 4-nitrophenol were confirmed by UV-vis spectroscopy.

ORGANIC DUST IN THE INTERSTELLAR MEDIUM

  • KWOK, SUN
    • 천문학논총
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    • 제30권2호
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    • pp.155-158
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    • 2015
  • The traditional view of dust in the interstellar medium is that it is made of graphite and silicates. In this paper, we discuss the evidence for complex organics being a major component of interstellar dust. Comparison between astronomical infrared spectra and laboratory spectra of amorphous carbonaceous materials suggests that organics of mixed aromatic-aliphatic structures are widely present in circumstellar, interstellar, and galactic environments. Scenarios for the synthesis of these compounds in the late stages of stellar evolution are presented.

Interlayers of polymer tandem solar cells

  • 김태희;김경곤
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2009년도 제38회 동계학술대회 초록집
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    • pp.318-318
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    • 2010
  • We present the effect of interlayers of polymer tandem solar cells on their photovoltaic performance. P-type and n-type interlayers are essential for the series-connection of the subcells and enable to form the tandem cell architecture by the solution processing. In this study, we use PEDOT:PSS, nanocrystalline $TiO_2$, and blends of semiconducting polymers and fullerene derivatives as a hole transporting layer, electron transporting layer, and photoactive layers, respectively. We show that photovoltaic performances of polymer tandem solar cells depending on various PEDOT:PSS layers with the different electric conductivity and the various $TiO_2$ layer thickness.

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Gas-Phase Technology and Microstructure of Fullerite Films

  • A.S. Berdinsky;Chun, Hui-Gon;Lee, Jing-Hyuk;Song, Yong-Hwa;Yu. V. Shevtsov
    • 한국표면공학회지
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    • 제37권2호
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    • pp.71-75
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    • 2004
  • The technology of $C_{60}$ fullerite films preparation by means of gas-phase deposition and structure of fullerite films are described. A three-channel flow plant was used to obtain fullerite films. The films were deposited in the flow of inert gas under reduced pressure onto a cooled silicon or sapphire substrate placed inside the reaction chamber of the plant. The plant allows one to obtain the films of pure fullerenes and to synthesise the films from fullerene compounds and doped fullerenes. The structure of two types of films were investigated by FE-SEM and SEM techniques: pure fullerite films onto silicon and sapphire substrates as well as compound films were studied by FE-SEM technique. All samples have shown columnar structure with high level of porosity. The synthesis of films composed of fullerene and its compounds for use in electronics is demonstrated to be promising. For example, experiments confirm the possibility to use fullerite films in sensor electronics to produce humidity and thermal sensors. It is also possible to use the sensitivity of these films to isotropic pressure. The experiments with $C_{60}$-Cu-J films have shown quite strong dependence of their resistance on pressure of different sort of medium-gas that could be used in gas-sensitive sensors. The structure and preparation technology of resistive sensor based on fullerite films are described.bed.

Study of Nano-scale Fullerene (C60) Clusters Formed in Micro-sized Droplet by UV Irradiation

  • Yeo, Seung-Jun;Ahn, Jeung-Sun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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    • pp.571-571
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    • 2012
  • We discovered the formation of C60 aggregates in solution by means of photoluminescence spectroscopic study on C60 in solutions. From the in-depth investigation of temperature dependence of the luminescence of C60 in toluene, benzene and CS2 solutions, we reported that the C60 aggregates are formed during cooling at the freezing temperature of these solvents. Furthermore, the C60 aggregates can be changed to stable structures by irradiating with UV pulse-laser (Nd:YAG laser, 355nm). As a consequence, we could obtain nano-scale photo-polymerized C60 clusters, which appear as round-shaped nano- scale particles in high resolution transmission electron-microscopy (HRTEM) images. However, the yield of the nano-scale C60 clusters obtained by this method is too small. So we designed and developed a system to obtain C60 cluster of macroscopic quantity by using ultrasonic nebulizer. In this system, C60 solution was vaporized to several micro-sized droplets in vacuum, resulting in the formation of C60 aggregates by evaporating solvent (toluene). The system was invented to produce nano-scale carbon clusters by the irradiation of UV light upon C60 aggregates in vacuum. We have characterized the products, C60 cluster, obtained from the system by using UV absorption spectra and HPLC spectra. Although the products have a possibility of inclusion various forms of C60 cluster, results support that the product formed from the system by using vaporizer method establishes a new method to obtain C60 cluster in macroscopic quantity. In the presentation, the details of the system and the results of characterization are reported.

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Design of an Electron Ohmic-Contact to Improve the Balanced Charge Injection in OLEDs

  • 박진우;임종태;염근영
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.283-283
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    • 2011
  • The n-doping effect by doping metal carbonate into an electron-injecting organic layer can improve the device performance by the balanced carrier injection because an electron ohmic contact between cathode and an electron-transporting layer, for example, a high current density, a high efficiency, a high luminance, and a low power consumption. In the study, first, we investigated an electron-ohmic property of electron-only device, which has a ITO/$Rb_2CO_3$-doped $C_{60}$/Al structure. Second, we examined the I-V-L characteristics of all-ohmic OLEDs, which are glass/ITO/$MoO_x$-doped NPB (25%, 5 nm)/NPB (63 nm)/$Alq_3$ (32 nm)/$Rb_2CO_3$-doped $C_{60}$(y%, 10 nm)/Al. The $MoO_x$doped NPB and $Rb_2CO_3$-doped fullerene layer were used as the hole-ohmic contact and electron-ohmic contact layer in all-ohmic OLEDs, respectively, Third, the electronic structure of the $Rb_2CO_3$-doped $C_{60}$-doped interfaces were investigated by analyzing photoemission properties, such as x-ray photoemission spectroscopy (XPS), Ultraviolet Photoemission spectroscopy (UPS), and Near-edge x-ray absorption fine structure (NEXAFS) spectroscopy, as a doping concentration at the interfaces of $Rb_2CO_3$-doped fullerene are changed. Finally, the correlation between the device performance in all ohmic devices and the interfacial property of the $Rb_2CO_3$-doped $C_{60}$ thin film was discussed with an energy band diagram.

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