• Title/Summary/Keyword: Electron transfer

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Study on Morphology Investigation and Electron-Transfer Property of Self-Assembled Viologen Monolayers (자기조립된 Viologen 단분자막의 모폴로지 관찰과 전하이동 특성 연구)

  • Lee, Dong-Yun;Park, Sang-Hyun;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.395-396
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    • 2005
  • We fabricated self-assembled monolayers(SAMs) onto quartz crystal microbalance(QCM) using viologen, which has been widely used as electron acceptor and electron transfer mediator. We determined the time dependence to resonant frequency shift during self-assembly process and observed the morphology of self-assembled mono layers by STM and investigated the electrochemical behavior of SAMs by cyclic voltammetry. Electrochemical deposition of viologen was investigated using electrochemical quartz crystal microbalance(EQCM). The redox reactions of viologen were highly reversible and the EQCM has been employed to monitor the electrochemically induced adsorption of SAMs during the redox reactions.

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Photoinduced Electron Tansfer of Microperoxidase-8

  • Su, Chien-Hua;Lin, Ren-Jay;Chang, I-Jy
    • Journal of Photoscience
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    • v.6 no.3
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    • pp.129-133
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    • 1999
  • Microperoxidase 8 (MP8) has been prepared by sequential hydrolysis of cytochrome C by pepsin and trypsin. This five-coordinated heme-octapetide fragment provides a uniques structure to evaluate the electronic coupling efficiency to the iron through axial position and porphyrin edge. At alkali pH, Ru(bpy)2(im)22+ is completely quenched in AcMP8Ru complex . Transient kinetics measurement showed the decay rate to be ~1 $\times$1012S-1. Ruthenium bipyridine complex with a carboxyl group substituted bipyridine has been prepared adn reacted with MR 8 to yield N-terminus bound RuMP8 complex. The luminescence decay rate has been measured as 1 $\times$109S-1. By using semiclassical electron transfer theory, we found the electron transfer efficiency through axial positioin of iron prophyrin is as good through prophyrin edge.

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Fabrication of 6, 13-bis(triisopropylsilylethynyl) (TIPS) pentacene -Nanowire Arrays Using Nano Transfer Molding

  • Oh, Hyun-S.;Sung, Myung-M.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.284-284
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    • 2010
  • We report a fabrication of 6, 13-bis(triisopropylsilylethynyl) (TIPS) pentacene nanowires that made on Si substrates by liquid bridge-nanotransfer molding (LB-nTM) with polyurethane acrylate (PUA) mold. LB-nTM is based on the direct transfer of various materials from a stamp to a substrate via a liquid bridge between them. In liquid bridge-transfer process, the liquid layer serves as an adhesion layer to provide good conformal contact and form covalent bonding between the TIPS-pentacene nanowire and the Si substrate. The patterned TIPS-Pentacene nanowires have been investigated by Atomic force microscopy (AFM), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM) and electrical properties.

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Excitation Hopping Behavior between Two Naphthy1 Moieties Spatially Fixed in Triptycene Structure

  • Lee, Bong
    • Korean Journal of Materials Research
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    • v.6 no.12
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    • pp.1242-1247
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    • 1996
  • Spatially fixed bichromophoric systems with nonidentical chromophores have been extensively employed for studies of electron transfer and excitation transfer. Excitation hopping behavior between two naphthy1 moieties on 7,14-dihydro-7,14-ethanodibenz[a,h] anthracene(DEA)has been explored by the time-resolved fluorescence anisotropy measurements. The experimentally obtained value of the hopping rate in DEA agrees at least qualitatively with that calculated on the basis of the Dexter's theory, but disagrees with that calculated on the basis of the Forster's theory, indicates that for a pair of donor and acceptor with inter-chromophore separation as short as 4.5 $\AA$, excitation transfer via electron exchange is a predominant process.

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Using Electron-beam Resists as Ion Milling Mask for Fabrication of Spin Transfer Devices

  • Nguyen Hoang Yen Thi;Yi, Hyun-Jung;Shin, Kyung-Ho
    • Journal of Magnetics
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    • v.12 no.1
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    • pp.12-16
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    • 2007
  • Magnetic excitation and reversal by a spin polarized current via spin transfer have been a central research topic in spintronics due to its application potential. Special techniques are required to fabricate nano-scale magnetic layers in which the effect can be observed and studied. This work discusses the possibility of using electron-beam resists, the nano-scale patterning media, as ion milling mask in a subtractive fabrication method. The possibility is demonstrated by two resists, one positive tone, the ZEP 520A, and one negative tone, the ma-N2403. The advantage and the key points for success of this process will be also addressed.

Computational Modeling of Cyclic Voltammetry on Multi-electron Electrode Reaction using Diffusion Model (확산모델을 이용한 다중전자 전극반응에 대한 순환전위법의 전산모델링)

  • Cho, Ha-Na;Yoon, Do-Young
    • Journal of the Korean Electrochemical Society
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    • v.15 no.3
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    • pp.165-171
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    • 2012
  • Here is implemented MATLAB program to analyze the characteristic curves of cyclic voltammetry which involves the multi-electron electrode reaction considered as key processes in electrochemical systems. For the electrochemical mass-transfer system, Fick's concentration equation subject to semi-infinite diffusion model for the boundary condition was discretized and solved by the explicit finite difference method. The resulting concentration values were converted into currents at each node by using Butler-Volmer equation. Based on the good agreement between the present numerical solution and the existing experimental results, effects of kinetic constants and CV scan rates on the reaction mechanism in multi-electron transfer processes were investigated effectively.

Quantum Yield of Photoinduced Electron Transfer Across Microemulsion Interfaces (마이크로 에멀젼 계면을 통과하는 광유발전자의 양자수득률)

  • Yong-Tae Park
    • Journal of the Korean Chemical Society
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    • v.27 no.3
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    • pp.213-217
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    • 1983
  • Devices that mimic the natural photosynthetic pathway are of considerable interest as fuel sources. Quantum yield of viologen radical formation in several water-in-oil microemulsion system were measured. The yield of hexadecylviologen radical formation in microemulsion system using EDTA as an electron donor, ruthenium bipyridinium complex as photosensitizer, and hexadecylviologen as an electron acceptor was 12%. When benzylnicotinamide was inserted in the interface of the microemulsion and azo compound was dissolved in oil face, the quantum yield of hydroazo compound was 0.16. Organic dye (Rose bengal) was used as photosensitizer for the photoinduced electron transfer reaction. In anionic microemulsion no electrontransfer was observed.

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