• 제목/요약/키워드: Electrochemical Property

검색결과 384건 처리시간 0.029초

Self-Assembled Monolayers of Dioctyl Diselenides on Au(111)

  • Choi, Jung-Seok;Lee, Yoon-Jung;Kang, Hun-Gu;Han, Jin-Wook;Noh, Jae-Geun
    • Bulletin of the Korean Chemical Society
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    • 제29권6호
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    • pp.1229-1232
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    • 2008
  • The surface structure, electrochemical behavior, and wetting property of self-assembled monolayers (SAMs) formed by dioctyl diselenide (DODSe) on Au(111) were investigated by scanning tunneling microscopy (STM), cyclic voltammetry (CV), and contact angle measurements. In contrast to the formation of well-ordered SAMs by octanethiol on Au(111), the SAMs formed by DODSe have a disordered phase and many unusual vacancy islands (VIs). In addition, the formation of DODSe SAMs is largely influenced by the solution concentration used. DODSe SAMs formed in 5 $\mu$ M and 50 $\mu$ M solutions have two mixed domains consisting of missing-row ordered phases and disordered phases, while DODSe SAMs formed in 1 mM and 5 mM solutions have only disordered phases with an abnormally high VI fraction of 22-24%. We also found that the wetting property and electrochemical behavior of DODSe SAMs on Au(111) are markedly influenced by the formation of ordered SAMs and the density of VIs.

전기화학법을 이용한 전해질 변화에 따른 Viologen 자기조립박막의 전하이동 특성 연구 (A Electron-Transfer Study on Self-Assembled Viologen Monolayer In different Electrolytes Using Electrochemical Process)

  • 이동윤;박상현;신훈규;박재철;장정수;권영수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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    • pp.878-881
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    • 2004
  • When it converted solar energy or light energy into chemical energy, it studied the electric charge transfer property of the viologen which is used widely as the electron acceptor for the electric charge delivery mediation of the devices. It was formed monolayer in QCM by self-assembled viologen. The absorbed quantities of viologen's electron through peak current and to analyze the electron transfer property of viologen in redox reaction made experiments in cyclic voltammetry among the electrochemical process. It studied the electron transfer relation of viologen from changing the anion in 0.1M NaCl and $NaClO_4$ electrolyte and the interrelation between scan rate and peak current when scan rate increased twice.

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Influence of Carbon Fiber on Corrosion Behavior of Carbon Steel in Simulated Concrete Pore Solutions

  • Tang, Yuming;Dun, Yuchao;Zhang, Guodong;Zhao, Xuhui;Zuo, Yu
    • Corrosion Science and Technology
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    • 제16권4호
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    • pp.175-182
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    • 2017
  • Galvanic current measurement, polarization curves, electrochemical impedance spectroscopy and weight loss test were used to study the corrosion behavior of carbon steel before and after carbon fibers coupling to the carbon steel in simulated concrete pore solutions, and the film composition on the steel surface was analyzed using XPS method. The results indicate that passive film on steel surface had excellent protective property in pore solutions with different pH values (13.3, 12.5 and 11.6). After coupling with carbon fibers (the area ratio of carbon steel to carbon fiber was 12.31), charge transfer resistance $R_{ct}$ of the steel surface decreased and the $Fe^{3+}/Fe^{2+}$ value in passive film decreased. As a result, stability of the film decreased and the corrosion rate of steel increased. Decreasing of the area ratio of steel to carbon fiber from 12.3 to 6.15 resulted in the decrease in $R_{ct}$ and the increase in corrosion rate. Especially in the pore solution with pH 11.6, the coupling leads the carbon steel to corrode easily.

방사선 그래프트법에 의해 제조된 탄소나노튜브 지지체를 기반으로 한 전기화학 미생물 바이오센서의 제작 (Fabrication of Electrochemical Microbial Biosensor Based on MWNT Supports Prepared by Radiation-Induced Graft Polymerization)

  • 신수란;권해두;최성호
    • 폴리머
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    • 제35권3호
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    • pp.216-222
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    • 2011
  • 4급 아민에 의한 이온성 및 3급 아민에 의한 비공유전자쌍의 이중 특성을 갖은 다중벽 탄소나노튜브 지지체를 글리시딜 메티크릴레이트의 방사선 그래프트법을 수행한 후, 아민화 반응을 수행하여 제조하였다. 제조된 이중 다중벽 틴소나노튜브 지지체와 나피온 용액을 혼합 후, 이 코팅용액을 GC 전극 표면에 코팅시킨 후, 여기에 미생물인 Alkaligenes spp.를 고정화하여 미생물 바이오센서를 제작하였다. 이 미생물 센서의 페놀에 대한 검출범위는 0.005~7.0 mM이었다. 이 미생물 바이이오센서를 이용하여 상용의 적포도주에서 페놀함량을 측정하였다.

탄소나노섬유/코발트산화물 복합전극의 케폐시턴스 특성 (Capacitance Property for a Carbon-nanofiber/Cobalt Oxide Composite Electrode)

  • 윤여일;고장면
    • 한국세라믹학회지
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    • 제45권8호
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    • pp.482-485
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    • 2008
  • Composite electrode consisting of carbon nanofiber (CNF) and cobalt oxide was prepared for supercapacitor electrode, and its electrochemical property was investigated by means of cyclic voltammetry. Cyclic voltammetric results for the composite electrode showed it had specific capacitance value of 420 F/g at 5 mV/s, which was higher than capacitance value of 180 F/g for the bare CNF. It is concluded that the capacitive property of CNF can be improved by coating cobalt oxide on it to increase the surface area of cobalt oxide.

마이크로 크기를 가지는 빗살무늬 그루우브 패턴의 빗살각도변화에 대한 실험적 마찰특성 (Sliding Friction Property of Angle Effect for Crosshatch Micro-grooved Pattern under Lubricated)

  • 김석삼;채영훈
    • 한국기계가공학회지
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    • 제10권3호
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    • pp.94-99
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    • 2011
  • Micro-scale surface pattern has an benefit of tribological application under lubricated sliding contact. Therefore, a special pattern, that has to reduce the coulomb friction under contact, is considered to be necessary for improved efficiency of machines. The current study investigated the friction property of angle effect for micro-scale grooved crosshatch pattern on bearing steel surface using pin-on-disk type. The samples fabricated by photolithography process and then these are carry out the electrochemical etching process. We discuss the friction property due to the influence of hatched-angle on contact surface. We could be explained the lubrication mechanism for a Stribeck curve. It was found that the friction coefficient depend on an angle of the crosshatch on contact surface. It was thus verified that micro-scale crosshatch grooved pattern could affect the friction reduction.