• Title/Summary/Keyword: electrochemical analysis

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Microfluidic platform for voltammetric analysis of biomolecules (Microfludic 플랫폼을 이용한 생체 분자의 voltammetric 분석)

  • Chand, Rohit;Han, Da-Woon;Jha, Sandeep K.;Kim, Yong-Sang
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.1686-1687
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    • 2011
  • A microfabricated chip with in-channel electrochemical cell using interdigitated gold electrode was fabricated for sensitive electrochemical analysis. The gold electrodes were fabricated on glass wafer using thermal evaporator and were covered using PDMS mold containing microchannel for analyte and electrolyte. The active area of each electrode was $250\;{\mu}m{\times}200\;{\mu}m$ with a gap of 200 ${\mu}m$ between the electrodes. Microelectrodes results in maximum amplification of signal, since the signal enhancement effect due to cycling of the reduced and oxidized species strongly depends on the inter electrode distance. Analytes such as methylene blue and guanosine were characterized using the fabricated electrodes and their electrochemical characteristics were compared with conventional bulk electrodes. The device so developed shall find use as disposable electrochemical cell for rapid and sensitive analysis of electroactive species.

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Electrochemical Approaches to Dye-Sensitized Solar Cells (염료감응 태양전지의 전기화학적 접근을 통한 해석)

  • Jo, Yim-Hyun;Lim, Jeong-Min;Nam, Hee-Jin;Jun, Yong-Seok
    • Journal of the Korean Electrochemical Society
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    • v.12 no.4
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    • pp.301-310
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    • 2009
  • This paper describes one of the hot issues in solar cell studies, dye-sensitized solar cell. DSSC is a kind of photoelectrochemical cells. Therefore, it is quite different from the conventional solar cells which originate from pn semiconductor theory, although its mechanism can be explained with the theory. This paper describes the difference between the conventional semiconductor approaches and a newly adapted one for DSSC. Especially, electrochemical analysis methods such as electrochemical impedance analysis and cyclic voltammogram are briefly introduced, which are commonly used for DSSC analysis.

Effect of Water Temperature on Generation of Ion Migration (이온 마이그레이션 발생에 대한 수분온도의 영향)

  • Lee Deok Bo;Kim Jung Hyun;Kang Soo Keun;Kim Sang Do;Jang Seok Won;Lim Jae Hoon;Ryu Dong Soo
    • Journal of Applied Reliability
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    • v.5 no.2
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    • pp.261-272
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    • 2005
  • In evaluation of electronic reliability on the PCB(Printed Circuit Board), electrochemical migration is one of main test objects. The phenomenon of electrochemical migration occurs In the environment of the high humidity and the high temperature under bias through a continuous aqueous electrolyte. In this paper, the generating mechanism of electrochemical migration is investigated by using water droll acceleration test under various waters. The waters used in the water drop test are city water, distilled water and ionic water. It found that the generated velocity of electrochemical migration depended on the temperature of water and the electrolyte quantity which included in the various waters.

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The influence of impedance on micro electrochemical machining (마이크로 전해가공에서 임피던스의 영향)

  • 강성일;주종길;박규열;전종업
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1893-1896
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    • 2003
  • This research aimed to fabricate a micro structure using micro electrochemical machining (${\mu}$-ECM). with a view to that the theory of ${\mu}$-ECM is established accurately in a different way of conventional electrochemical machining. In details, if the impedance is existed in the system, it is difficult to analyze the micro electrochemical reaction efficiently in polarization curve using a potentiodynamic test. Hence, this research investigates the relationships between impedance and electric current measuring with a potentiostatic test applying to a pair or electrode as a constant potential. And this paper examines the influence of temperature of electrolyte on polarization curve for the quantitative analysis of electrochemical reactions.

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Electrochemical Study on the Coumarin Derivatives

  • Kim, Il Kwang;Chun, Hyun Ja;Paik, Soon Ok;Park, Sung Woo
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.655-661
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    • 1995
  • The electrochemical reduction of coumarin derivatives in 0.1M TEAP acetonitrile solution was investigated by the direct current, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. The electrochemical reduction of 7-acetoxy-4-bromomethyl-coumarin(ABMC) was proceeded as an irreversible three steps(-0.58, -1.63 and -2.25 volts) of electrochemical transfer before chemical reaction. The solution color turned to yellow after the carboxyl group was reduced at 2nd step(-1.63 volts vs. Ag-AgCl) and the change in color was independant to the bromo group. Upon the basis of the results on the products analysis and the interpretaton of polarograms, a possible electrochemical reaction mechanism was suggested.

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Electrochemical Determination of Chemical Oxygen Demand Based on Boron-Doped Diamond Electrode

  • Dian S. Latifah;Subin Jeon;Ilwhan Oh
    • Journal of Electrochemical Science and Technology
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    • v.14 no.3
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    • pp.215-221
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    • 2023
  • A rapid and environment-friendly electrochemical sensor to determine the chemical oxygen demand (COD) has been developed. The boron-doped diamond (BDD) thin-film electrode is employed as the anode, which fully oxidizes organic pollutants and provides a current response in proportion to the COD values of the sample solution. The BDD-based amperometric COD sensor is optimized in terms of the applied potential and the solution pH. At the optimized conditions, the COD sensor exhibits a linear range of 0 to 80 mg/L and the detection limit of 1.1 mg/L. Using a set of model organic compounds, the electrochemical COD sensor is compared with the conventional dichromate COD method. The result shows an excellent correlation between the two methods.