• 제목/요약/키워드: Cyclic Voltammetry.

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Triphenylphosphine Phenylimide의 전기화학적인 환원 (Electrochemical Reduction of Triphenylphosphine Phenylimide)

  • 박종민
    • 대한화학회지
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    • 제18권5호
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    • pp.341-353
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    • 1974
  • Triphenylphosphine phenylimide의 비수용액에서의 전기화학적인 환원반응을 polarography, cyclic voltammetry, controlled-potential coulometry 및 electron spin resonance 법을 써서 고찰하였다. 이 유기인화합물은 one-electon transfer에 따라서 anion radical이 형성되나 순간일 뿐이고 protonation과 재차 one-electon reduction 결과 인과 질소사이의 이중결합이 끊어진다. 그 결과 아닐린이 주요 반응생성물로서 발견되었다. 또 한편 동반하는 화학반응결과 생긴 주산물의 하나인 triphenylposphine oxide의 환원결과 인과 페닐 사이의 단일결합이 끊어지는 것도 관찰할 수 있었다.

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Synthesis of Ordered Mesoporous Manganese Oxides by Double Replication for Use as an Electrode Material

  • Guo, Xiao-Feng;Kim, Geon-Joong
    • Bulletin of the Korean Chemical Society
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    • 제32권1호
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    • pp.186-190
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    • 2011
  • Periodically ordered mesoporous manganese oxides were synthesized in a single and double replication procedure. Mesoporous SBA-15 and -16 silica and their reverse replica carbons were successively used as hard templates. The silica and carbon pore systems were infiltrated with $Mn(NO_3)_2{\cdot}xH_2O$ or $Mn(AcAc)_2$, which was then converted to $Mn_2O_3$ at 873 K; the silica and carbon matrix were finally removed by NaOH solution or calcinations in air. The structure of the mesoporous $Mn_2O_3$, using a carbon template, corresponds to that of the original SBA-15 and SBA-16 silica. The products consist of hexagonally arranged cylindrical mesopores with crystalline pore walls or cubic mesoporous pores. The structure of replica has been confirmed by XRD, TEM analysis, and its electrochemical properties were tested with cyclic voltammetry. Formation of $Mn_2O_3$ inside the mesoporous carbon pore system showed much improved electrical properties.

Study on Charge Transfer Characteristics of Self-Assembled Viologen Monolayers

  • Park Sang-Hyun;Lee Dong-Yun;Kwon Young-Soo
    • KIEE International Transactions on Electrophysics and Applications
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    • 제5C권4호
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    • pp.161-164
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    • 2005
  • Viologen has been extensively investigated in the paper because their well-behaved electrochemistry has led to their use in a variety of theses, including the electron acceptor for the electric charge delivery mediation of the devices. It was formed monolayer in QCM by self-assembly method. We could know the adsorbed mass of viologen molecules from the frequency shift. We calculated that the adsorbed mass was about 196 [$ng/cm^2$]. We studied the electron transfer property of viologen by the cyclic voltammetry among the electrochemical process so we changed an anion like 0.1 M $NaClO_4$ and $Na_3PO_4$ electrolyte solution and investigated the interrelationship between scan rate and peak current when scan rates were increased twice.

전기변색 $MoO_3$ 박막의 열처리 효과 (Annealing Effects of The Electrochromic $MoO_3$ Thin Films)

  • 임동규;이진민;조봉희;김동진;김영호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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    • pp.505-508
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    • 1999
  • The effect of the heat treatment on electrochromic properties of $MoO_3$ thin films is investigated by studing optical modulation, optical density, response time, and cyclic voltammetry. From the results of XRD analysis, heat-treated at $450^{\circ}C$ in air for 1 hour $MoO_3$ thin films are found to be crystalline while as-deposited film and heat-treated at low temperature (${\leq}300^{\circ}C$) are amorphous. The electrochrornic devices using as-deposited $MoO_3$ films exhibits good electrochromic properties compare to those using the heat treated $MoO_3$ films. It has shown that the heat-treatment affected the stability and the electrochromic properties of $MoO_3$ films.

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Electrochemical and Spectroscopic Studies on the Interaction between DNA and the Product of Enzyme-catalyzed Reaction of OPD-H2O2-HRP

  • Niu, S.Y.;Zhang, S.S.;Ma, L.B.;Jiao, K.
    • Bulletin of the Korean Chemical Society
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    • 제25권6호
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    • pp.829-832
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    • 2004
  • The pure product of 2,3-diaminophenazine was prepared by the enzyme-catalyzed reaction of ophenylenediamine-$H_2O_2$-horseradish peroxidase and characterized by UV/Vis spectroscopy, IR spectroscopy and NMR spectroscopy. The electrochemical behaviour of 2,3-diaminophenazine on the glassy carbon electrode was studied. The interaction between 2,3-diaminophenazine and deoxyribonucleic acid was studied by cyclic voltammetry method and UV/Vis spectroscopy, which indicated that the interaction between them is intercalation. The influence of reacting time was also studied. The binding ratio of the 2,3-diaminophenazine-DNA complex is calculated to be 1 : 2 and the binding constant is to be $5.07{\times} 10^3L{\cdot}mol^{-1}$ at room temperature.

Voltammetric Study of Anionic Surfactant-Modified Glassy Carbon Electrode for Bis(2,2'-Bipyridyl)Copper(II) in 200 mM NaBr

  • Ko, Young Chun
    • 통합자연과학논문집
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    • 제7권2호
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    • pp.120-123
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    • 2014
  • When a hydrophobic and hydrophilic environments of bis(2,2'-bipyridyl) copper(II) ($Cu(bpy)_2{^{2+}}$) are produced in the presence of anionic surfactant sodium dodecyl sulfate (SDS), cyclic voltammetry is used to investigate the microscopic environments which occurs at the glassy carbon electrode. In order to see the relation between ${\Delta}E_p$ and a critical micelle concentration (CMC), ${\Delta}E_p$ vs. -Log[SDS] for the redox couples are plotted. The concentration at the intersection of two lines is 2.57 mM SDS, and this concentration can be determined as the CMC (relative error: below 0.03%; 2.63 mM SDS by surface tensiometry).

리튬 2차전지용 전해액의 초성 및 비교 분석 (Mixture of the Lithium Secondary Batteries and Analyses)

  • 임동규;김영호;조봉희;우병원;나두찬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.395-397
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    • 1999
  • There are many efforts to improve electrolytes to satisfy the requirements of a lithium rechargeable battery. We have investigated a binary solvent mixture containing the electrolyte lithium salt($LiBF_4$, $LiPF_6$), that is conductive and electrochemically stable. Ionic conductivities were measured between -5 and $80^{\circ}C$, and cyclic voltammetry between 2.5 and 4.3 V were measured by SUS or platinum electrode.

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Electrochemical Characteristics of 5,10,15,20-Tetrakis-Octadecyloxymethylphenyl-Porphyrin-Zn(II) Langmuir-Blodgett (LB) Films

  • Koo, Ja-Ryong;Choi, Don-Soo;Kim, Young-Kwan;Kim, Jung-Soo
    • KIEE International Transactions on Electrophysics and Applications
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    • 제11C권3호
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    • pp.58-62
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    • 2001
  • Since Metallo-Porphyrin (MP) is very interesting compound due to its unique electronic and redox properties and it is also chemically and thermally stable, MP has been studied for potential memory and switching devices. In this study, thin films of 5,10,15,20-Tetrakis-Octadecyloxymethylphenyl-Porphyrin-Zn(II) were prepared by the Langmuir-Blodgett (LB) method and characterized by using UV/vis absorption spectroscopy and cyclic voltammetry. It was found that the proper transfer surface pressure for film deposition was 25 mN/m and the limiting area per molecule was 135 ${\AA}^2$/molecule. The current-voltage (I-V) characteristics of these films were investigated. Further details on the electrical properties of Porphyrin-Zn(II) derivative films will be discussed.

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Electrochemical Behaviors of ABTS2- on the Thiol-modified Gold Electrodes

  • Kim, Hyug-Han
    • 전기화학회지
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    • 제9권3호
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    • pp.113-117
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    • 2006
  • The electrochemical properties of the redox mediator, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) ($ABTS^{2-}$) were studied using cyclic voltammetry. The measured potentials (${E^o}'$ vs SCE) of the two redox couples of ABTS are 0.45 V for $ABTS^{2-}/ABTS^{\cdot-}$ and 0.87 V for $ABTS^{\cdot-}/ABTS^0$. The rate constant for heterogeneous electron transfer and the diffusion coefficients for $ABTS^{2-}$ are $5x10^{-3}cm\;s^{-1}$ and $3.1x10^{-6}cm^2\;s^{-1}$, respectively. Our interest in $ABTS^{2-}$ stems from the fact that this molecule functions as a substrate to the copper oxidase, laccase, by providing the reducing equivalents necessary for the biocatalyzed reduction of dioxygen to water. Consequently, when laccase is tethered to an electrode surface or dissolved in solution, $ABTS^{2-}$ can be used to quantify enzyme activity electrochemically.

Comparative electrochemical study of sulphonated polysulphone binded graphene oxide supercapacitor in two electrolytes

  • Mudila, Harish;Zaidi, M.G.H.;Rana, Sweta;Alam, S.
    • Carbon letters
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    • 제18권
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    • pp.43-48
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    • 2016
  • Sulphonated polysulphone (SPS) has been synthesized and subsequently applied as binder for graphene oxide (GO)-based electrodes for development of electrochemical supercapacitors. Electrochemical performance of the electrode was investigated using cyclic voltammetry in 1M Na2SO4 and 1M KOH solution. The fabricated supercapacitors gave a specific capacitance of 161.6 and 216.8 F/g with 215.4 W/kg and 450 W/kg of power density, in 1M Na2SO4 and 1M KOH solutions, respectively. This suggests that KOH is a better electrolyte than Na2SO4 for studying the electrochemical behavior of electroactive material, and also suggests SPS is a good binder for fabrication of a GO based electrode.