• Title/Summary/Keyword: Cyclic voltammetry

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Methodological Consideration on the Prediction of Electrochemical Mechanical Polishing Process Parameters by Monitoring of Electrochemical Characteristics of Copper Surface

  • Seo, Yong-Jin
    • Journal of Electrochemical Science and Technology
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    • v.11 no.4
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    • pp.346-351
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    • 2020
  • The removal characteristics of copper (Cu) from electrochemical surface by voltage-activated reaction were reviewed to assess the applicability of electrochemical-mechanical polishing (ECMP) process in three types of electrolytes, such as HNO3, KNO3 and NaNO3. Electrochemical surface conditions such as active, passive, transient and trans-passive states were monitored from its current-voltage (I-V) characteristic curves obtained by linear sweep voltammetry (LSV) method. In addition, the oxidation and reduction process of the Cu surface by repetitive input of positive and negative voltages were evaluated from the I-V curve obtained using the cyclic voltammetry (CV) method. Finally, the X-ray diffraction (XRD) patterns and energy dispersive spectroscopy (EDS) analyses were used to observe the structural surface states of a Cu electrode. The electrochemical analyses proposed in this study will help to accurately control the material removal rate (MRR) from the actual ECMP process because they are a good methodology for predicting optimal electrochemical process parameters such as current density, operating voltage, and operating time before performing the ECMP process.

Electrochemical Behavior and Square Wave Voltammetric Determination of Doxorubicin Hydrochloride

  • Hahn, Young-Hee;Lee, Ho-Young
    • Archives of Pharmacal Research
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    • v.27 no.1
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    • pp.31-34
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    • 2004
  • The electrochemical behavior of doxorubicin hydrochloride was investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). From CV and SWV studies of doxorubicin hydrochloride in the acetate buffers of various pH values, it was found that protons were involved in the reduction of the antibiotic at the $H^+/e^$- ratio at one ( $\DeltaEp/pH =-53 ∼ -61 mV at 23^{\circ}C$), proposing the electrochemical reduction of the quinone moiety in its anthraquinone aglycone. Its electrochemical behavior was pseudo-reversible in the acetate buffer of pH 3.5 by exhibiting the well-defined single cathodic and anodic waves and the ratio of $lp^a/lp^c$ at approximately one over the scan rates of 10∼100 mV/s. Fast and sensitive SWV showing a single peak of doxorubicin has been applied for its quantitative analysis using an acetate buffer of pH 3.5. A linearity was obtained when the peak currents (lp) were plotted against concentrations of doxorubicin in the range of $5.0\times10^{-7} M∼1.0\times10^{-5}$M with a detection limit of $1.0\times10^{-7}$ M.

Electrochemistry Characterization of Metal Using Corrosion Inhibitors Containing Amide Functional Group (아미드 작용기를 가진 부식억제제를 사용한 금속의 전기화학적 특성)

  • Park, Keun-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.28 no.1
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    • pp.48-56
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    • 2011
  • In this study, we investigated the C-V diagrams and metal surface related to the electrochemistry characterization of metal(nickel, SUS-304). We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate were 50, 100, 150, 200 and 250 mV/s. As a result, the C-V characterization of metal using N,N-dimethylacetamide and N,N-dimethylformamide inhibitors appeared irreversible process caused by the oxidation current from the cyclic voltammogram. After adding organic corrosion inhibitors, adsorption film constituted, and the passive phenomena happened. According to the results by cyclic voltammetry method, it was revealed that the addition of inhibitors containing amide functional group enhances the corrosion resistance properties.

Bioelectrochemical Denitrification by Pseudomonas sp. or Anaerobic Bacterial Consortium

  • Park, Doo-Hyun;Park, Yong-Keun
    • Journal of Microbiology and Biotechnology
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    • v.11 no.3
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    • pp.406-411
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    • 2001
  • In a bacterial denitrification test with Pseudomonas sp. and anaerobic consortium, more nitrates and less substrate were consumed but less metabolic nitrite was produced under an anaerobic $H_2$ condition rather than under $N_2$ condition. In a bioelectrochemical denitrification test with the same organisms, the electrochemically reduced neutral red was confirmed to be a substitute electron donor and a reducing power like $H_2$. The biocatalytic activity of membrane-free bacterial extract, membrane fraction, and intact cell for bioelectrochemical denitrification was measured using cyclic voltammetry. When neutral red was used as an electron mediator, the electron transfer from electrode to electron acceptor (nitrate) via neutral red was not observed in the cyclic voltammogram with the membrane-free bacterial extract, but it was confirmed to gradually increase in proportion to the concentration of nitrate in that of the membrane fraction and the intact cell of Pseudomonas sp.

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Voltammetric Study of Surfactant-Modified Carbon Electrode: $Ru(ph){_3}^{2+}$ in Sodium Dodecyl Sulfate Solution

  • Ko, Young Chun;Chung, Keun Ho
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.643-648
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    • 1995
  • Cyclic voltammetric method is used to survey microscopic environments which take place at the surfactant-modified carbon electrode when the hydrophobic and hydrophilic environments of $Ru(ph){_3}^{2+}$(tris 1,10-phenanthroline ruthenium(II) chloride) is created by the addition of anionic surfactant, sodium dodecyl sulfate(SDS). Critical micelle concentration(CMC) of SDS in $Ru(ph){_3}^{2+}$ measured by cyclic voltammetry(CV) is in aggrement with that by surface tensiometry. Influence of the concentration of supporting electrolyte at surfactant-modified carbon electrode is investigated.

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Electrochemistry Characterization of Nickel Using Ethanolamine Compound Additives (에탄올아민화합물 첨가에 대한 니켈의 전기화학적 특성)

  • Park, Keun-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.27 no.4
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    • pp.531-538
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    • 2010
  • The electrochemistry characterization of metal is important in many industrial applications. In this study, we investigated the C-V diagrams related to the electrochemistry characterization of nickel. We determined electrochemical measurement by using cyclic voltammetry with a three electrode system. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650mV and measured to the initial point. The scan rate were 100, 150, 200 and 200mV/s. As a result, the C-V characterization of nickel using ethanolamine and ethylethanolamine inhibitor appeared irreversible process caused by the oxidation current from the cyclic voltammogram. After adding ethanolamine compound additive, adsorption film constituted, and the passive phenomena happened. According to the results by cyclic voltammetry method, it was revealed that the effect of the electrochemistry characterization of nickel depends on ethanolamine structure interaction to adsorption complex.

A Cyclic Voltammetric Study of Electrodes for Reverse Electrodialysis

  • Lee, Seo-Yoon;Lee, Dong-Ju;Yeon, Kyeong-Ho;Kim, Woo-Gu;Kang, Moon-Sung;Park, Jin-Soo
    • Journal of the Korean Electrochemical Society
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    • v.16 no.3
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    • pp.145-150
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    • 2013
  • In this study, the electrochemical investigation of various electrodes for reverse electrodialysis using potassium ferrocyanide and potassium ferricyanide as a redox system was carried out. Cyclic voltammetry was the employed method for this electrochemical study. From the results of cyclic voltammograms for various electrode materials, i.e., Au, Vulcan supported Pt, activated carbon, carbon nanofiber, Vulcan, the Vulcan electrode showed the lowest overpotential, but the Pt electrode having slightly higher overpotential obtained slightly higher anodic and cathodic current densities for the $Fe(CN)_6{^{4-}}/Fe(CN)_6{^{3-}}$ redox couple. The cyclic voltammograms for the Vulcan electrode confirmed very good electrochemical reversibility and kinetic behavior. As a result, among the electrode materials, the Vulcan electrode is the most promising electrode material for reverse electrodialysis.

Determination of Fluoroquinolone Antibacterial Agents by Square Wave Adsorptive Stripping Voltammetry (네모파 흡착 벗김 전압전류법에 의한 플루오로퀴놀론 계 항생제의 검출)

  • Boo, Han-Kil;Song, Youn-Joo;Park, Se-Jin;Chung, Taek-Dong
    • Journal of the Korean Electrochemical Society
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    • v.13 no.1
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    • pp.63-69
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    • 2010
  • Electrochemical behavior of fluoroquinolone antibacterial agents on carbon paste electrode (CPE) were investigated by cyclic voltammetry and square wave adsorptive stripping voltammetry. The fluoroquinolone antibacterial agents tested in this study were Enrofloxacin (ENR), Norfloxacin (NOR), Ciprofloxacin (CIP), Ofloxacin (OFL) and Levofloxacin (LEV). In acetate buffer at pH 4.5, the oxidation peak potentials of the fluoroquinolone antibacterial agents of ENR, NOR, CIP, OFL, and LEV were 0.952 V, 1.052 V, 1.055 V, 0.983 V, and 0.990 V (vs. Ag/AgCl), respectively. And their oxidation peak currents from square wave adsorptive stripping voltammograms are proportional to the concentration of each antibacterial agent over the range from $0.2\;{\mu}M$ to $1\;{\mu}M$.