• 제목/요약/키워드: Buckminsterfullerene

검색결과 8건 처리시간 0.029초

Ohmic Contact for Hole Injection Probed by Dark Injection Space-Charge-Limited Current Measurements

  • Song, Ok-Keun;Koo, Young-Mo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.1061-1064
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    • 2009
  • Through dark injection space-charge-limited current (DI-SCLC) and trap-free SCLC measurements, it has been demonstrated that an indium tin oxide (ITO)/buckminsterfullerene ($C_{60}$) electrode can form a quasi-Ohmic contact with N, N'-bis (naphthalen-1-yl)-N, N'-bis(phenyl) benzidine (NPB). The DI-SCLC results show a clear peak current along with a shift of the peak position as the field intensity varies, implying an Ohmic (or quasi-Ohmic) contact. A theoretical simulation of the SCLC also shows that ITO/$C_{60}$ forms an Ohmic contact with NPB. The Ohmic contact makes it possible to estimate the NPB hole mobility through the use of both DI-SCLC and trap-free SCLC analysis. This also contributes to a reduction in power consumption.

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Electrochemical Properties of Buckminsterfullerene ($C_{60}$) in Acetonitrile Containing Quarternary Ammonium Electrolytes

  • Kim, Il Kwang;Kim, Hyun Jin;Oh, Gi Su;Jeon, Il Chol;Ahn, Byoung Joon
    • 분석과학
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    • 제8권4호
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    • pp.675-682
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    • 1995
  • Thin films of buckminsterfullerene($C_{60}$) formed by solution drop casting on Pt foil electrode surfaces were studied by cyclic voltammetry(CV) in acetonitrile(MeCN) containing quaternary ammonium or alkali-metal salts as supporting electrolyte. The electrochemical behaviors of $C_{60}$ films are found to be strongly dependent on the nature of the supporting electrolytes, especially with tetrabutyl ammonium perchlorate (TBAP, $NBu_4ClO_4$), and tetrabutyl ammonium tetrafluoroborate ($TBABF_4$, $NBu_4BF_4$). Reasonably stable films are formed into which electrons can be injected. The interaction of $C_{60}$ film with the quaternary ammonium cation may produce the fulleride salts $(TBA^+)(C{_{60}}^-)$ and $(TBA^+)_2(C{_{60}}^{2-})$. The bulk electroreduction with a controlled potential to generate the soluble $C{_{60}}^{3-}$ anions(dark red-brown color) is followed by electrooxidative deposition to produce a neutral $C_{60}$ film on the surface. The peak currents($I_{pc}$ and $I_{pa}$) of these thin film were dramatically decreased with repetitive potential scanning. These results could be explained by the adsorption-desorption phenomena and ion pairing interaction of reduced species($C{_{60}}^-$, and $C{_{60}}^{2-}$) onto the electrode surface. The peak current changes and peak potential shifts of the thin $C_{60}$ film in cyclic voltammograms formed from solution were observed by varying scan rates.

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풀러렌의 성질과 반응 (Reactions and Properties of Fullerene ($C_{60}$))

  • 임충선;홍성규;고원배
    • Elastomers and Composites
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    • 제45권2호
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    • pp.74-79
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    • 2010
  • 논문에서는 풀러렌의 성질, 유기반응, 고분자반응을 설명하였으며, 풀러렌과 고분자의 블렌딩에 대해 소개를 하였다. 또한 다른 화학물질과 풀러렌의 반응성을 기술하였다. 풀러렌의 화학 반응은 가지 사슬 풀러렌 고분자, 주사슬 풀러렌 고분자, 별 모양 풀러렌 고분자, 덴드리머 타입 풀러렌 고분자와 같은 연구에 응용되었다.

Electronic Structures of a Macrocyclic Fulleropyrrolidine

  • 황선구;이종명;전일철
    • Bulletin of the Korean Chemical Society
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    • 제17권12호
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    • pp.1112-1117
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    • 1996
  • The electronic structures of twenty-seven isomers of a macrocyclic fulleropyrrolidine are investigated with semi-empirical extended Huckel (EH) molecular orbital method. The geometry of each isomer is determined by the molecular mechanics and dynamics methods based on UFF (universal force field) empirical force field. The calculated geometries, such as the carbon-carbon distances of the fullerene moiety, are in good agreement with those of related fullerene derivatives. The EH calculation shows that the formation of macrocyclic pyrrolidine ring on fullerene moiety results in the reduction of the HOMO-LUMO energy gap. From the graphical analysis of the DOS (density of states), PDOS (projected DOS), and MOOP (molecular orbital overlap population) curves, we can find that this reduction is due to splitting of the HOMO of fullerene moiety, which results from the symmetry-breaking and the distortion of the buckminsterfullerene framework from its ideal icosahedral structure.

$C_{60}$ 얇은 결정의 결정구조에 관한 투과형전자현미경 연구 (A TEM Investigation on the Crystal Structure of $C_{60}$ Thin Crystals)

  • 송세안;김성훈;서영덕;김성근
    • Applied Microscopy
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    • 제21권2호
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    • pp.67-75
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    • 1991
  • [ $C_{60}$ ] molecule, the Buckminsterfullerene, has generated great interest because of its unique molecular structure and of superconductivity exhibited in its alkali-doped solids. We have investigated the molecular stacking and crystal structure of $C_{60}$ thin crystals formed on amorphous carbon film. The $C_{60}$ powder which was chromatographically purified was dissolved in benzene. The thin crystals of $C_{60}$ were observed with a 300 keV transmission electron microscope. Electron diffraction analysis and direct imaging of its molecular stacking were carried out. It was found from this work that the molecules of $10.0{\AA}$ diameter are arrayed hexagonally on substrate surface and $8.7{\AA}$ lattice planes are quite often found in several types of ED patterns, which can never be explained with a fcc model. Therefore the structure of $C_{60}$ thin crystals is hcp, although we cannot fully exclude the possibility of co-existence of hcp and fcc.

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저분자 유기 광다이오드 소자의 p형 유기물 두께에 따른 전류 특성에 관한 연구 (A Study on the Thickness Dependence of p-type Organic Layer on the Current of Small Molecule-based Organic Photodiode)

  • 김영우;이동운;전용민;조의식;권상직
    • 반도체디스플레이기술학회지
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    • 제22권3호
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    • pp.101-105
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    • 2023
  • Organic photo Diodes (OPDi) give multiple advantages in the growing interest of the flexible optoelectronic devices. Organic semiconductors are freeform as they can deposit on any substrate, so it could be flexible. But the inorganic material photodiodes (PDs) are usually fabricated on silicon wafers which are solid. So, normally PDs are inflexible. By those reasons, we decided to make the vacuum deposited small molecule OPDi. We have investigated the OPDi's J-V characteristic by changing the thickness of p-type layer of OPDi. This device consists of indium-tin-oxide (ITO) / 2,3:6,7-dibenzanthracene (pentacene) / buckminsterfullerene (C60) / aluminum (Al). Its J-V characteristics were measured in the probe station(4156C) that can give dark condition while measuring. And for the luminance characteristics, the photocurrent was measured with the bright halogen lamp and a probe station.

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