• 제목/요약/키워드: Catalytic electrode

검색결과 191건 처리시간 0.024초

과산화수소 정량을 위한 장미조직 함유 바이오센서의 전기화학 속도론적 고찰 (Electrochemical Kinetic Assessment of Rose Tissue Immobilized Biosensor for the Determination of Hydrogen Peroxide)

  • 유근배
    • 공업화학
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    • 제25권1호
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    • pp.107-112
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    • 2014
  • 흑연가루의 결합재로 클로로술폰화 폴리에틸렌 고무용액을, 매개체로 ferrocene을 사용하여 장미조직을 고정한 과산화수소 정량 바이오센서를 제작하였다. 실험 전극전위 영역에서 보여준 Hanes-Woolf 도시의 선형성은 기질의 환원이 장미 과산화효소의 촉매력에 의한 것임을 보여 주었다. 또 얻어진 10개 이상의 전기화학 파라미터들은 전극이 정량적으로 성능을 발휘하고 있음을 입증하였다. 이런 사실들은 효소전극의 실용화를 위하여 장미조직이 상업용 과산화효소를 대치하여 사용될 수 있음을 확신시켜 주는 것이었다.

Studies on Electrochemical properties of Lithium/Oxyhalide Cell: Electrocatalytic Effects on the Reduction of Thionyl Chloride

  • Kim Woo Seong;Choi Yong-Kook;Chjo Ki-Hyung
    • Bulletin of the Korean Chemical Society
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    • 제15권6호
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    • pp.456-460
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    • 1994
  • Catalytic effects of various cobalt phenylporphyrin compounds on the reduction of thionyl chloride at glassy carbon electrode have been evaluated by determining kinetic parameters with cyclic voltammetric techniques. The concentration of catalysts and the electrode immersion time have been found to affect the catalyst performance strongly, leading to a conclusion that the compounds are first adsorbed at the electrode surface and act as catalysts. Significant improvements in cell performance have been noted in terms of both exchange rate constants of up to 3 times and current densities of up to 150% at glassy carbon electrode.

Electro-Catalytic Behavior of an Antiarrhythmic Drug, Procainamide and its Electro-Analytical Applications

  • Abbar, Jyothi C.;Meti, Manjunath D.;Nandibewoor, Sharanappa T.
    • Journal of Electrochemical Science and Technology
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    • 제9권4호
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    • pp.292-300
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    • 2018
  • The electrocatalytic oxidative behavior of an antiarrhythmic drug, procainamide hydrochloride (PAH) at the gold electrode surface has been examined using different voltammetric methods like cyclic, linear-sweep and differential pulse voltammetry. Voltammograms obtained in this study reveal that the electrode exhibit excellent electrocatalytic activity towards oxidation of the drug. The parameters that can affect the peak current at different pH, scan rate and concentration were evaluated. The number of electrons transferred was calculated. The current displayed a wide linear response ranging from 0.5 to $30.0{\mu}M$ with a limit of detection of 56.4 nM. The impact of potential interfering agents was also studied. The electrode displayed wide advantages such as simple sample preparation, appreciable repeatability, reproducibility and also high sensitivity. Furthermore, the feasibility of the proposed method was successfully demonstrated by determining PAH in the spiked human biological sample.

Improvement in Catalytic Activity of Ag Catalyst via Simple Mixing with Carbon

  • Choun, Myounghoon;Baek, Ji Yun;Eom, Taehyoung
    • KEPCO Journal on Electric Power and Energy
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    • 제5권4호
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    • pp.331-335
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    • 2019
  • In this study we investigate catalytic activity and selectivity of mixture of Ag and ketjenblack according to their ratios by product analysis and electrochemical experiments, such as cyclic voltammetry, linear sweep voltammetry and chronoamperometry. We reveal that catalytic activity toward CO2 reduction to CO is improved by simple mixing Ag nanoparticle and ketjenblack because addition of ketjenblack suppresses aggregation of Ag nanoparticles and brings increase in electrochemical active surface area. However, excess amount of ketjenblack rather inhibit the CO2 reduction to CO. These observations provide clues to develop highly active Ag catalyst or electrode toward electrochemical reduction of CO2.

고체 고분자 연료전지용 비백금계 산소환원촉매 조성 조사 및 분석 (Composition Survey and Analysis of Non-Pt Oxygen Reduction Catalysts for Proton Exchange Membrane Fuel Cells)

  • 권경중
    • 전기화학회지
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    • 제15권1호
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    • pp.12-18
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    • 2012
  • 다양한 응용분야에서 활용될 수 있는 고체고분자연료전지의 경우 현재 상용화에 가장 큰 걸림돌이 되고 있는 것이 고가의 백금 촉매이다. 따라서 특히 최근 들어 산소환원반응에서 백금을 대체하는 물질을 개발하기 위한 연구가 전세계적으로 확산되고 있다. 그러나 촉매 개발 시 경제성 관점 외에 내구성도 고려해야 하는데, 이런 관점에서 백금과 유사한 물성과 활성이 기대되는 백금족 원소들이 한 대안이 될 것이다. 가장 백금과 유사한 물성, 활성을 나타내는 팔라듐과 칼코겐화물 형태의 루테늄이 지금까지 가장 많이 연구가 되었으며 상대적으로 이리듐, 로듐, 오스뮴은 산소환원 촉매로 많은 연구가 되지 않았다. RDE (rotating disk electrode)를 이용한 반쪽전지 실험이나 연료전지 MEA (membrane electrode assembly) 운전을 통하여 백금과 활성을 비교해보면 팔라듐 계열의 비백금 촉매가 가장 백금에 가까운 활성을 나타내고 있음을 알 수 있다. 이 논문에서는 각 백금족 원소들 기반의, 현재까지 문헌상으로 보고된 촉매조성들을 분석하여 비백금 산소환원 촉매 개발에 도움이 되고자 한다.

Pt-ZnO 상대전극을 가지는 염료감응형 태양전지의 광전변환 특성 분석 (Enhanced catalytic activity of Pt counter electrodes employing ZnO nanorods for dye-sensitized solar cells)

  • 이정관;천종훈;양현석;김재홍
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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    • pp.118.2-118.2
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    • 2011
  • In order to increase the energy conversion efficiency of dye-sensitized solar cells (DSSCs), we employed a counter electrode that was platinum coated using a doctor blade technique on synthesized ZnO nanostructures on fluorinedoped tin oxide (FTO). The ZnO nanostructures possessing high electrochemical activity and large surface area of the counter electrode were grown by a chemical bath deposition (CBD) method at various times, 2, 4, and 8 h. The efficiency of DSSC with the Pt-ZnO counter electrode was improved 7.01% (grown for 2 h), 7.63% (grown for 4 h), and 6.13% (grown for 8 h), respectively. Compared with a standard DSSC without ZnO nanostructures, whose efficiency was 6.27%, the energy conversion efficiency increased approximately 22% for the DSSC with the Pt-ZnO (grown for 4 h) electrode. It indicates that the Pt coated on the ZnO nanostructure improves the electrocatalytic activity of the counter electrode.

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Integrated Microdisk Gold Electrode Modified with Metal-porphyrin and Metal-phthalocyanines for Nitric Oxide Determination in Biological Media

  • Kim, Il-Kwang;Bae, Hyun-Ok;Oh, Gi-Soo;Chung, Hun-Taeg;Kim, Young-Jin;Chun, Hyun-Ja
    • Bulletin of the Korean Chemical Society
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    • 제24권11호
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    • pp.1579-1584
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    • 2003
  • An integrated gold microdisk electrode was constructed and modified with metal-porphyrin or metal-phthalocyanines for NO determination in biological media. Microanalysis of NO using square wave anodic stripping voltammetry in $1\;{\times}\;10^{-2}$ M $HClO_4$ was optimal when the accumulation potential was 0.1 V, frequency 100 Hz, and the scan rate was 200 mV/s. When the electrode was modified with metal-porphyrin or metal-phthalocyanines, the anodic peak currents of NO increased due to the catalytic oxidation of NO. In case of Fe(II)-phthalocyanine modified electrode, the peak currents remarkably increased and the sensitivity was high. The calibration curve had good linearity in the range from $3.6\;{\times}\;10^{-5}$ M to $7.2\;{\times}\;10^{-7}$ M, and the detection limit was $5.7\;{\times}\;10^{-7}$ M. For the structural stability and increased sensitivity, Fe(II)-phthalocyanine modified gold microdisk electrode coated with Nafion was applied to determination of NO released from cultured macrophase.

Viologen 박막을 이용한 과산화수소의 전기화학적 검출 특성 (Electrochemical Detection of Hydrogen Peroxide based on Viologen Monolayers)

  • 최원석;이동윤;박상현;박재철;권영수
    • 전기학회논문지
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    • 제57권11호
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    • pp.2006-2010
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    • 2008
  • In this paper, we fabricated a biosensor for detecting hydrogen peroxide and investigated the sensing property. We prepared a viologen and hemoglobin modified gold electrode using self-assembly and layer by layer method. The electrochemical property of the viologen derivative was characterized in 0.1 M $NaClO_4$ electrolyte solution by cyclic voltammetry. The modified electrode showed reversible electrochemical properties and high stability. From the results, the viologen can act as a charge transfer mediator for access to the electrode surface. The catalytic characteristics of the designed sensor proved that hemoglobin has been kept in its natural structure and can retain its biological activity. The designed biosensor showed a fast amperometric response, excellent linearity and low detection limit. In addition, it had high sensitivity, good reproducibility and stability.

금속이 첨가된 탄소전극의 전기화학적 특성과 이를 이용한 L-lactate 바이오센서의 개발 (Electrocatalytic Properties of Metal-dispersed Carbon Paste Electrodes for Reagentless L-lactate Biosensors)

  • 윤현철;김학성
    • KSBB Journal
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    • 제11권4호
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    • pp.489-496
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    • 1996
  • Carbon paste electrode를 채용함으로써 L-lac tate 측정용의 전기화학식 바이오센서를 성공적으로 개발할 수 있었다. 특히 뛰어난 electrocatalytic activity를 갖는 platinum이 첨가된 platinum-CPE 를 이용하여 낮은 전위에서의 NADH의 전기척 산 화가 가능하였다. Enzyme (lactate dehydrogen­a ase)과 $NAD^+$를 carbon paste형식으로 직접 제조 함으로써 L-lactate 측정을 위한 성공적인 바이요센 서의 개발이 가능하였다. 위와 같은 개발연구를 통 하여 다른 $NAD^+$ -dependent dehydrogenase를 채 용한 바이오센서로의 적용이 기대된다.

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