• Title/Summary/Keyword: Cyclic Voltammetry (CV)

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Fundamentals of cyclic voltammetry (순환 전압전류법의 기초)

  • Shin, Ka Yoon;Oum, Wansik;Yu, Dong Jae;Kang, Sukwoo;Kim, Eun Bi;Kim, Hyoun Woo
    • Journal of Sensor Science and Technology
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    • v.30 no.6
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    • pp.384-387
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    • 2021
  • Cyclic voltammetry (CV) is a powerful electrochemical measurement technique that can determine redoxable substances in a solution. The advantage of CV is that we can observe redox behavior over a wide potential range in a short time. Because of its practicality and versatility, CV is used not only in electrochemistry but also in various fields of chemistry, such as inorganic chemistry, organic chemistry, and biochemistry. As technology advances and the popularity of CV grows, the need for trained electrochemists also increases. However, most students do not receive formal training in these technologies as part of their curriculum. There are few concise and accessible resources for learning CV. Therefore, this manuscript provides a brief introduction to cyclic voltammetry to aid readers in collecting and interpreting useful data from cyclic voltammograms.

Characteristic Analysis of Cyclic Voltammetry on a Self-Assembled Mono-layer Electrode (자가조립 단층 전극에 대한 순환전위법의 특성해석)

  • Cho, Hana;Yoon, Do-Young
    • Journal of the Korean Electrochemical Society
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    • v.16 no.4
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    • pp.217-224
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    • 2013
  • In this paper, we have investigated the characteristics of cyclic voltammetry of a self-assembled mono-layer(SAM) electrode which was modified by 3-Mercaptopropionic acid (3-MPA) on gold nanoparticle(AuNP)-deposited electrode. Also, the transport phenomena of electrons and ions around the electrode have been analyzed. The governing equation and its boundary conditions by adopting the semi-infinite diffusion model were formulated for the mass-transfer dominant system. In order to obtain the numerical solutions of cyclic voltammetry(CV) on SAM electrodes, MATLAB program was implemented by applying the explicit finite difference method. Resulting CV program for the SAM-modified electrode was verified in good agreements with the experimental CV results for the 3-MPA on AuNP electrode.

Adsorptive Behavior of Catechol Violet and Its Thorium Complex on Mercury Electrode in Aqueous Media

  • Rabia Mostafa K. M.
    • Journal of the Korean Electrochemical Society
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    • v.7 no.1
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    • pp.9-15
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    • 2004
  • Cyclic voltammetry and chronocoulometry have been used for characterization of catechol violet (CV) at the hanging mercury drop electrode in acetic acid-sodium acetate buffer solution. At pH 2.94 a nearly symmetric cyclic voltammetric wave due to an irreversible weak adsorption of CV on mercury was obtained at concentration of $0.53{\mu}mol\;dm ^{-3}$. Under these conditions, CV adsorbes in a monolayer. Upon increasing the concentration, the symmetry of the wave decreases; it can be attributed to a mixed diffusion adsorption process. The amount of the adsorbed catechol violet on the HMDE expressed as surface concentration as well as the surface areaf occupied by one molecule$(\sigma)$ were calculated. It was found that the values obtained for f and o utilizing cyclic voltammetric and chrono-coulometry are almost identical. A 1:1 and 1:2 Th (IV)-CV complexes are formed on addition of thorium (IV) to catechol violet. These complexes are adsorbed and reduced on the HMDE at more negative potentials than the peak potential of free CV, Using the square-wave (SW) technique, the adsorptive cathodic stripping voltammetry, ACSV, of these complexes was studied. It was found that the SW-ACSV of Th(IV)-CV can be applied to the determination of thorium at the nanomole level. Optimum conditions and the analytical method of determination were presented and discussed.

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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    • 2009.06a
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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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Applications of Voltammetry in Lithium Ion Battery Research

  • Kim, Taewhan;Choi, Woosung;Shin, Heon-Cheol;Choi, Jae-Young;Kim, Ji Man;Park, Min-Sik;Yoon, Won-Sub
    • Journal of Electrochemical Science and Technology
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    • v.11 no.1
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    • pp.14-25
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    • 2020
  • Li ion battery (LIB) is one of the most remarkable energy storage devices currently available in various applications. With a growing demand for high-performance batteries, the role of electrochemical analysis for batteries, especially, electrode reactions are becoming very important and crucial. Among various analytical methods, cyclic voltammetry (CV) is very versatile and widely used in many fields of electrochemistry. Through CV, it is possible to know electrochemical factors affecting the reaction voltage and reversibility, and furthermore, quantitative analysis on Li+ diffusivity as well as intercalation and capacitive reactions, and also anionic redox reaction. However, the explanation or interpretation of the results of CV is often deficient or controversial. In this mini-review, we briefly introduce the principle of cyclic voltammetry and its applications in LIB to bring a better understanding of the electrochemical reaction mechanisms involved in LIB.

Voltammetric Assay of Silver Ions in Frog's Tissue

  • Ly, Suw-Young;Lee, Jin-Hui;Lee, Chang-Hyun
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.1
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    • pp.139-145
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    • 2013
  • The electrochemical analysis of silver ion was performed using cyclic voltammetry (CV) and square-wave (SW) stripping voltammetry, and electrode cell systems were fabricated with graphite pencil electrode (GE) of working, reference and counter electrodes. Also electrolyte was the use of sea water as electrolyte solutions instead of ionic controlled solutions. The optimum analytical conditions for the cyclic and stripping parameters were determined using GE. The results approached the microgram working ranges of SW(ug/L) and CV(ug/L) Ag, and the optimum conditions were applied to frog's tissue and the food samples.

Application of CV Cycling to the Activation of the Polymer Electrolyte Membrane Fuel Cell (고분자 전해질막 연료전지의 활성화를 위한 CV 활성화법)

  • Cho, Ki-Yun;Jung, Ho-Young
    • Applied Chemistry for Engineering
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    • v.23 no.5
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    • pp.445-449
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    • 2012
  • The activation process of the membrane-electrode assembly (MEA) is important for the mass production of the polymer electrolyte membrane fuel cell. The conventional activation process for the MEA requires excessive time and hydrogen gas and it might become the barrier for the commercialization of the fuel cell. The conventional activation process is based on hydrolysis of ion conducting membrane. In the study, we suggest the cyclic voltammetry (CV) technique as an on-line activation process and the CV activation process consists of two steps : 1) the humidification of the polymer electrolyte membrane and the electrode with 100% RH humidified nitrogen ($N_{2}$) gas, and 2) the removal step of the oxide layer on the surface of the Pt catalyst with CV cycling. The cycling reduces the activation time of the MEA by 2.5 h and use of hydrogen gas by 1/4.

Electrochemical Impedance Spectroscopy and Cyclic Voltammetry Methods for Monitoring SmCl3 Concentration in Molten Eutectic LiCl-KCl

  • Shaltry, Michael R.;Allahar, Kerry N.;Butt, Darryl P.;Simpson, Michael F.;Phongikaroon, Supathorn
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.18 no.1
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    • pp.1-18
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    • 2020
  • Molten salt solutions consisting of eutectic LiCl-KCl and concentrations of samarium chloride (0.5 to 3.0 wt%) at 500℃ were analyzed using both cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The CV technique gave the average diffusion coefficient for Sm3+ over the concentration range. Equipped with Sm3+ diffusion coefficient, the Randles-Sevcik equation predicted Sm3+ concentration values that agree with the given experimental values. From CV measurements; the anodic, cathodic, and half-peak potentials were identified and subsequently used as a parameter to acquire EIS spectra. A six-element Voigt model was used to model the EIS data in terms of resistance-time constant pairs. The lowest resistances were observed at the half-peak potential with the associated resistance-time constant pairs characterizing the reversible reaction between Sm3+ and Sm2+. By extrapolation, the Voigt model estimated the polarization resistance and established a polarization resistance-concentration relationship.

Trapezoidal Cyclic Voltammetry as a Baseline for Determining Reverse Peak Current from Cyclic Voltammograms

  • Carla B. Emiliano;Chrystian de O. Bellin;Mauro C. Lopes
    • Journal of Electrochemical Science and Technology
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    • v.15 no.3
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    • pp.405-413
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    • 2024
  • Several techniques for determining the reverse peak current from a cyclic voltammogram (CV) for a reversible system are described in the literature: CV itself as a baseline with long switching potential (Eλ) that serves as a baseline for other CVs, Nicholson equation that uses CV parameters to calculation reverse peak current and linear extrapolation of the current obtained at the switching potential. All methods either present experimental difficulties or large errors in the peak current determination. The paper demonstrates, both theoretically and experimentally, that trapezoidal cyclic voltammetry (TCV) can be used as a baseline to determine anodic peak current (iap) with high accuracy and with a switching potential shorter than that used by CV, as long as Eλ is at least 130 mV away from the cathodic peak. Beyond this value of switching potential the electroactive specie is completely depleted from the electrode surface. Using TCV with Eλ = 0.34 V and a switching time (tλ) of 240 s as a baseline, the determination of the reverse peak current presents a deviation from the expected value of less than 1% for most of the CVs studied (except cases when Eλ is close to the direct potential peak). This result presents better accuracy than the Nicholson equation and the linear extrapolation of the current measured at the switching potential, in addition to presenting a smaller error than that obtained in the acquisition of the experimental current. Furthermore, determining the reverse peak current by extrapolating the linear fit of iap vs. ${\sqrt[1/]{t_{\lambda}}}$ to infinite time gave a reasonable approximation to the expected value. Experiments with aqueous potassium hexacyanoferrate (II) and ferrocene in acetonitrile confirmed the theoretical predictions.

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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    • 2008.06a
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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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