• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.197-203
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• 2013

The diagnostic assay of calcium ion was sought using a modified sensor with square-wave stripping voltammetry (SWSV) and cyclic voltammetry (CV). In this study, simple graphite pencil was used as working, reference, and auxiliary electrodes. By coating the working electrodes with DNA, their sensitivity was very much improved, and good results were yielded. Moreover, clean seawater was used as an electrolyte solution instead of acid and base electrolytes to lessen the expenses involved in the experiment. The analytical optimum conditions were also examined. These conditions were attained at the low detection limit of $0.6ugL^1$. After that, the results were applied to drinking water of milk contain.

• Journal of the Korean Electrochemical Society
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• v.16 no.1
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• pp.30-38
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• 2013

In this study, a catalyst slurry was prepared with a Pt/C catalyst, Nafion ionomer solution as a binder, an ionic liquid (IL) (1-butyl-3-methylimidazolium tetrafluoroborate), deionized water and ethanol as a solvent for the application to polymer electrolyte fuel cells (PEFCs) at high-temperatures. The effect of the IL in the electrode of each design was investigated by performing a cyclic voltammetry (CV) measurement. Electrodes with different IL distributions inside and on the surface of the catalyst electrode were examined. During the CV test, the electrochemical surface area (ESA) obtained for the Pt/C electrode without ILs gradually decreased owing to three mechanisms: Pt dissolution/redeposition, carbon corrosion, and place exchange. As the IL content increased in the electrode, an ESA decrement was observed because ILs leaked from the Nafion polymer in the electrode. In addition, the CVs under conditions simulating leakage of ILs from the electrode and electrolyte were evaluated. When the ILs leaked from the electrode, minor significant changes in the CV were observed. On the other hand, when the leakage of ILs originated from the electrolyte, the CVs showed different features. It was also observed that the ESA decreased significantly. Thus, leakage of ILs from the polymer electrolyte caused a performance loss for the PEFCs by reducing the ESA. As a result, greater entrapment stability of ILs in the polymer matrix is needed to improve electrode performance.

• Journal of the Korean Electrochemical Society
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• v.13 no.2
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• pp.123-127
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• 2010

An assembled-graphite/DSA(Dimensionally Stable Anode) was prepared using graphite powder to increase durability and energy efficiency of redox flow battery and investigated its electrochemical properties in vanadium-based electrolyte. The cyclic voltammetry (CV) was carried out in the voltage range of -0.7V and 1.6V vs. SCE at 5 mV/sec scan rate to analyze vanadium redox reaction. From the CV results, the assembled-graphite/DSA electrode showed a fast couple reaction and good reversibility in 2M $VOSO_4$ + 2.5 M $H_2SO_4$ electrolyte. Therefore, it has been expected that this electrode increases power density as well as energy density of redox flow battery.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.863-866
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• 2011

The electrode reaction of $Eu^{3+}$ in a LiCl-KCl eutectic melt has been re-examined using cyclic voltammetry (CV). In this work, for the first time, the kinetic details of a $Eu^{3+}/Eu^{2+}$ redox system have been completely elucidated, along with the thermodynamic property, through a curve fitting applied to experimental CV data, which were obtained in a wide scan rate range of 0.5 to 10 V/s. The simulated results showed an excellent fit to all experimental CV data simultaneously, even though the curve fittings were performed within a large dynamic range of initial transfer coefficient values, formal potentials, and standard rate constants. As a result, a proper formal potential, transfer coefficient, and standard rate constant for the $Eu^{3+}/Eu^{2+}$ redox system were successfully extracted using the CV curve fitting.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.356-358
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• 2007

본 논문에서는 농도가 다른 EC계의 전해질 용액 중에서 흑연의 Cyclic voltammetry(CV)를 측정하였다. CV후 전극표면에 생성된 SEI를 투과형 전자현미경으로 분석한 결과, PC계에서 얻어지는 결과와 유사하게 충 방전 반응 및 생성된 SEI의 성질이 전해질의 농도에 크게 의존하고 있음을 확인하였다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.05a
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• pp.227-228
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• 2017

In this paper, electrolytic behavior of Cerium and Ce-Bi ion system was studied. The electrochemical behavior of Ce was studied in $LiCl-KCl-CeCl_3$ molten salts using electrochemical techniques Cyclic Voltammetry on tungsten electrodes at 773K. During the process of CV electrolysis, intermetallic compound were observed of Ce, Cex-Biy. Further study, in order to determine clarity of diffusion coefficient in this experiment, we will compare result of electrochemistry method and we also need to quantitative research.

• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.208-215
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• 2006

A simply prepared graphite, pencil-type working electrode was utilized to monitor fenitrothion concentrations, using the cyclic voltammetry (CV) and square-wave (SW) stripping voltammetry methods. The optimum conditions for analysis were sought. A very low detection limit was obtained compared to that obtained when other common voltammetry methods are used. The optimal parameters of the pencil-type electrode were found to be as follows: a pH of 3.7, a frequency of 500 Hz, an SW amplitude of 0.1 V, an increment potential of 0.005 V, an initial potential of -0.9V, and a deposition time of 500 sec. The analytical detection limit was determined to be 6.0 ngL-1 (2.16410-11 molL-1) fenitrothion at SW anodic and CV, and the relative standard deviation at the fenitrothion concentration of SW anodic 10 ugL-1 was 0.30% (n = 15) under the optimum conditions. Analysis was directly conducted through in-vivo real-time assay.

• Analytical Science and Technology
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• v.20 no.4
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• pp.289-295
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• 2007

A simple electric circuit of an infrared photodiode electrode (IPDE) was utilized to monitor iron using square-wave (SW) anodic stripping voltammetry (SV) and cyclic voltammetry (CV). The optimum analytical conditions were determined and were compared with those of common working electrodes. The comparison showed that CV is more sensitive and convenient to use than the common voltammetry methods. At the optimized conditions, the working ranges of 0.1- to 0.8- and 0.85- to 6.0 mg/L iron was obtained. Relative standard deviation of 15 measurements of iron (0.4 mg/L) was 0.09%. The analytical detection limit was found to be $80{\pm}0.6ug/L$, which was applied to iron in waste water.

• Journal of the Korean Electrochemical Society
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• v.19 no.3
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• pp.95-100
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• 2016

A method for electrochemical degradation of the perchlorate anion ($ClO_4{^-}$) using mercury film electrode has been studied. Electrochemical method has relatively simple pre-treatment. However, electrochemical method should avoid interference from hydrogen evolution at the applied potential to degradation of perchlorate ion, and thus applied electrode should have large hydrogen overvoltage which suppressed the hydrogen evolution at the working reduction potential to prevent hydrogen evolution. In this study, we used mercury film electrode as a working electrode which has a large overvoltage. Ag / AgCl (sat. NaCl) was used as a reference electrode, and platinum was used as a counter electrode. Mercury film electrode was made by cyclic voltammetry (CV) method. The deposition time was decided as 10 minute, and the stability of the mercury electrode in perchlorate solution was confirmed by CV. The reduction potential of perchlorate was checked by using CV method, and decomposition of perchlorate was performed by using chronoamperometric (CA) method. Also, ion chromatography (IC) was used to confirm the degradation rates of perchlorate.

• Transactions on Electrical and Electronic Materials
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• v.15 no.5
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• pp.257-261
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• 2014

Multilayered CdTe/PSS films were prepared by the electrostatic self-assembly method in an aqueous medium. Positively-charged cadmium telluride (CdTe) nanoparticles and anionic polyelectrolyte, poly (sodium 4-styrene sulfonate) (PSS) were assembled alternately in order to build up a multilayered film structure. A linear proportion of absorbance to the number of bilayers suggests that an equal amount of CdTe was adsorbed after each dipping cycle, which resulted in the buildup of a homogenous film. The binding energies of elements (Cd and Te) in multilayered CdTe/PSS film shifted from those of the CdTe nanoparticles in the pure state. This result indicates that the interfacial electron densities were redistributed by the strong electrostatic interaction between the oppositely-charged CdTe and PSS. Electrochemical properties of the multilayered CdTe/PSS films were studied in detail by cyclic voltammetry (CV).