• Title, Summary, Keyword: Linear sweep voltammetry

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The Determination of Germanium(IV) by Linear Sweep Voltammetry and UV-VIS Spectrophotometry (Linear Sweep Voltammetry와 UV-VIS Spectrophotometry를 이용한 게르마늄 분석)

  • Choi, Won-Hyung;Lee, Jin-Sik;Kim, Jae-Soo;Kim, Do-Hun
    • Analytical Science and Technology
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    • v.5 no.1
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    • pp.7-15
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    • 1992
  • Germainium(IV) was determined in perchloate supporting electrolyte solution containing phenylfluorone by hanging mercury drop electrode(HMDE) of Linear Sweep Voltammetry(LSV) and in hydrochloric acid solution by UV-VIS Spectrophotometry. The complex germanium(IV) with phenylfluorone was shown linear calibration curve in the range of $2.5{\sim}80{\mu}g/L$ by LSV and in the range of $10{\sim}300{\mu}g/L$ by UV-VIS Spectrophotometry.

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Semi-Circular Potential Sweep Voltammetry: Electrochemically Quasi-Reversible System

  • Park, Kyungsoon;Hwang, Seongpil
    • Journal of Electrochemical Science and Technology
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    • v.11 no.4
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    • pp.379-383
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    • 2020
  • The novel voltammetry using a semi-circular potential wave for quasi-reversible charge transfer system on electrode is theoretically investigated. Compared with conventional voltammetry based on linear sweep such as linear sweep voltammetry (LSV), semi-circular potential sweep voltammetry (SCV) may decrease the charging current outside the center of potential range and increase the faradaic current at the midpoint due to variable scan rate. In this paper, we investigate the system based on macroelectrode where simple 1 dimensional (1 D) diffusion system is valid with various charge transfer rate constant (k0). In order to observe the amplification at midpoint, voltammetric response with different midpoint ranging from -200 mV to 200 mV are studied. SCVs shows both the shift of peak potential and the amplification of peak current for quasi-reversible electrode reaction while only higher peak current is observed for reversible reaction. Moreover, the higher current at midpoint enable the amplification of current at low overpotential region which may assist the determination of onset potential as a figure-of-merit in electrocatalyst.

Eletrochemical Detection of Gene using Microelectrode-array DNA Chip (미소전극어레이형 DNA칩을 이용한 유전자의 전기화학적 검출)

  • ;;Eiichi Tamiya
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.7
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    • pp.729-737
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    • 2004
  • In this paper, a DNA chip with a microelectrode array was fabricated using microfabrication technology. Several probe DNAs consisting of mercaptohexyl moiety at their 5 end were immobilized on the gold electrodes by DNA arrayer. Then target DNAs were hybridized and reacted with Hoechst 33258, which is a DNA minor groove binder and electrochemically active dye. Linear sweep voltammetry or cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. It was derived from Hoechst 33258 concentrated at the electrode surface through association with formed hybrid. It suggested that this DNA chip could recognize the sequence specific genes.

Comparison of Hydrogen Crossover Current Density by Analysis Method of Linear Sweep Voltammetry(LSV) in Proton Exchange Membrane Fuel Cells (고분자전해질연료전지에서 선형주사전압전류측정법(LSV)의 분석방법에 따른 수소투과전류밀도 비교)

  • Oh, Sohyeong;Hwang, Byungchan;Lee, Mooseok;Lee, Donghoon;Park, Kwonpil
    • Korean Chemical Engineering Research
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    • v.56 no.2
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    • pp.151-155
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    • 2018
  • Degree of membrane degradation in Proton Exchange Membrane Fuel Cells (PEMFC) is mainly evaluated by the hydrogen crossover current density. The hydrogen crossover current density is measured by linear sweep voltammetry (LSV), which differs from the DOE protocol and the NEDO protocol. In this study, two protocols were compared during PEMFC operation and accelerated stress test. In the LSV method by the DOE method, the scan rate change affects the hydrogen crossover current density, but the NEDO method does not affect the hydrogen crossover current density. In the course of 15,000 cycles of polymer membrane wet/dry cycle, the DOE method was sensitive to membrane degradation, but the NEDO method was less sensitive to membrane degradation than the DOE method.

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.

Effect of copper surface to $HNO_3$ electrolyte ($HNO_3$ 전해액이 Cu 표면에 미치는 영향)

  • Park, Sung-Woo;Han, Sang-Jun;Lee, Young-Kyun;Lee, Woo-Sun;Seo, Yong-Jin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.123-123
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    • 2008
  • 본 논문에서는 Cu의 ECMP 적용을 위해 $HNO_3$ 전해액의 active, passive, transient, trans-passive 영역을 I-V 특성 곡선을 통해 알아보았고, LSV (Linear sweep voltammetry)와 CV (Cyclic voltammetry)법을 통하여 전기화학적 특성을 비교 분석하였다.

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Electrochemical Gene Detection Using Microelectrode Array on a DNA Chip

  • Park, Yong-Sung;Kwon, Young-Soo;Park, Dae-Hee
    • KIEE International Transactions on Electrophysics and Applications
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    • v.4C no.4
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    • pp.145-148
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    • 2004
  • In this study, a DNA chip with a microelectrode array was fabricated using microfabrication technology. Several probe DNAs consisting of mercaptohexyl moiety at their 5' end were immobilized on the gold electrodes by a DNA arrayer. Then target DNAs were hybridized and reacted with Hoechst 33258, which is a DNA minor groove binder and electrochemically active dye. Linear sweep voltammetry or cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. It was derived from Hoechst 33258 and concentrated at the electrode surface through association with the formed hybrid. This suggested that this DNA chip could recognize the sequence specific genes.

Determination of Ag(I) at a Chemically Modified Electrode Based on 2-Imino-cyclopentane-dithiocarboxylic Acid

  • Jeong-Sik Yeom;Mi-Sook Won;Sung-Nak Choi;Yoon-Bo Shim
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.200-205
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    • 1990
  • Chemically modified electrodes(CMEs), based on 2-imino-1-cyclopentane-dithiocarboxylic acid (icdc) containing carbon paste, have been characterized using cyclic voltammetric techniques. Ag(I) was chemically deposited on the CMEs, and voltammograms were obtained with the electrode in a separate buffer solution. The CME surface can be regenerated with exposure to acid and reused for deposition. In 10 deposition/measurement/regenerate cycles, the linear response have been reproduced up to $1{\times}10^{-6}$ M in linear sweep voltammetry and 1${\times}$10-8 M in differential pulse voltammetry with relative standard deviation of 5.2% and 12.4%, respectiveiy. The sensitivity increased with deposition time and scanning rate, and detection limit was $1{\times}10^{-7}M\;and\;1{\times}10^{-9}M$ at 20 minutes deposition in the linear sweep voltammetry and differential pulse voltammetry, respectively. The presence of some metal ions does not influence the silver ion response. Satisfactory results were obtained for the analysis of the silver ion for a variety of reference materials without interference of Hg ion at the condition of pH = 5-6.

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Effect of copper surface to $HNO_3$ and $KNO_3$ electrolyte ($KNO_3$$HNO_3$ 전해액이 Cu에 미치는 영향)

  • Seo, Yong-Jin;Han, Sang-Jun;Park, Sung-Woo;Lee, Young-Kyun;Lee, Sung-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • pp.486-486
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    • 2009
  • In this paper, the current-voltage (I-V) curves, such as linear sweep voltammetry (LSV) and cyclic voltammetry (CV), were employed to evaluate the effect of electrolyte concentration on the electrochemical reaction trend. From the I-V curve, the electrochemical states of active, passive, transient and trans-passive could be characterized. And then, we investigated that how this chemical affect the process of voltage-induced material removal in electrochemical mechanical polishing (ECMP) of Copper. The scanning electron microscopy (SEM) and energy dispersive spectroscopy EDS) analyses were used to observe the surface profile. Finally, we monitored the oxidation and reduction process of the Cu surface by the repetition of anodic and cathodic potential from cyclic voltammetry (CV) method in acid- and alkali-based electrolyte. From these analyses, it was important to understand the electrochemical mechanisms of the ECMP technology.

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Genomic Detection using Electrochemical Method (전기화학적 방법에 의한 유전자의 검출)

  • Choi, Yong-Sung;Lee, Kyung-Sup;Park, Dae-Hee
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.6
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    • pp.560-570
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    • 2005
  • In this paper, a microelectrode away DNA chip was fabricated on glass slide using photolithography technology. Several probe DNAs consisting of mercaptohexyl moiety at their 5' end were immobilized on the gold electrodes by DNA arrayer utilizing the affinity between gold and sulfu. Then target DNAs were hybridized and reacted with Hoechst 33258, which is a DNA minor groove binder and electrochemically active dye. Cyclic voltammetry in 5mA ferricyanide/ferrocyanide solution at 100 mV/s confirmed the immobilization of probe DNA on the gold electrodes. Linear sweep voltammetry or cyclic voltammetry showed a difference between target DNA and control DNA in the anodic peak current values. It was derived from Hoechst 33258 concentrated at the electrode surface through association with formed hybrid. It suggested that this DNA chip could recognize the sequence specific genes. It suggested that multichannel electrochemical DNA microarray is useful to develop a portable device for clinical gene diagnostic system.