• Title/Summary/Keyword: Pt electrode

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Amperometric Morphine Detection Using Pt-Co Alloy Nanowire Array-modified Electrode

  • Tao, Manlan;Xu, Feng;Li, Yueting;Xu, Quanqing;Chang, Yanbing;Wu, Zaisheng;Yang, Yun-Hui
    • Bulletin of the Korean Chemical Society
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    • v.31 no.7
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    • pp.1968-1972
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    • 2010
  • Pt-Co alloy nanowire array was directly synthesized by electrochemical deposition with polycarbonate template at -1.0V and subsequent chemical etching of the template. The use of Pt-Co alloy nanowire array-modified electrode (Pt-Co NAE) for the determination of morphine (MO) is described. The morphology of the Pt-Co alloy nanowire array has been investigated by scanning electron microscopy (SEM) and energy disperse X-ray spectroscopy (EDS) analysis), respectively. The resulting Pt-Co NAE offered a linear amperometric response for morphine ranging from $2.35\times10^{-5}$ to $2.39\times10^{-3}$ M with a detection limit of $7.83\times10^{-6}$ M at optimum conditions. This sensor displayed high sensitivity and long-term stability.

Optimization of Platinum amount in Pt/C for PEMFC (PEMFC 용 Pt 담이 촉매의 Pt 담지비에 따른 성능변화)

  • Cho Y.H.;Cho Y.H.;Park H.S.;Sung Y.E.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.547-548
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    • 2006
  • This study focuses on a determination of amount of Pt in the Pt/C for catalysts of polymer electrolyte membrane fuel cells (PEMFC). PEMFC offer low weight and high power density and being considered fur automotive and stationary power applications. The PEMFC behavior is quite complex is influenced by several factors, including catalysts and structure of electrode and membrane type. Catalyst of electrode is important factor for PEMFC. One of the obstacles preventing polymer electrolyte membrane fuel cells from commercialization is the high cost of noble metals to be used as catalyst, such as platinum. To effectively use these metals, they have to be will dispersed to small particles on conductive carbon supports. The optimal amount of Pt in Pt/C was investigated by using polarization curves in single cell with $H_2/O_2$ operation.

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The Investigation of Electro-Oxidation of Methanol on Pt-Ru Electrode Surfaces by in-situ Raman Spectroscopy

  • She, Chun-Xing;Xiang, Juann;Ren, Bin;Zhong, Qi-Ling;Wang, Xiao-Cong;Tian, Zhong-Qun
    • Journal of the Korean Electrochemical Society
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    • v.5 no.4
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    • pp.221-225
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    • 2002
  • Assisted by the highly sensitive confocal microprobe Raman spectrometer and proper surface roughening procedure, the Raman investigation on the adsorption and reaction of methanol was performed on Pt-Ru electrodes with different coverages. A detailed description of the roughening process of the Pt electrodes and the underpotential deposition of the Ru was given. Reasonably good Raman signal reflecting the metal-carbon vibration and CO vibration was detected. The appearance of vibrations of the Ru oxides, together with the existence of Ru-C, Pt-C and CO bands, clearly demonstrates the participation of the bi-functional mechanism during the oxidation process of methanol on Pt-Ru electrodes. The Pt-Ru electrode was found to have a higher catalytic activity over Pt electrodes. This preliminary study shows that electrochemical Raman spectroscopy can be applied to the study of rough electrode surface.

Photovoltaic Efficiency Characteristics of DSSC with Electroplated Pt/Ni Counter Electrode (백금/니켈 전기 도금 상대전극을 사용한 염료 감응형 태양전지 광전 변환 효율 특성)

  • Hwang, Ki Seob;Doh, Seok Joo;Ha, KiRyong
    • Applied Chemistry for Engineering
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    • v.22 no.1
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    • pp.98-103
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    • 2011
  • We prepared a counter electrode by electroplating Ni as underlayer and Pt as plating layer on the FTO glass to increase the efficiency of dye-sensitized solar cell (DSSC). We found an excellent adhesion between Ni underlayer and FTO glass when Ni underlayer was electroplated at $10mA/cm^2$ for 2 min on FTO glass. We observed Ni and Pt metal diffraction peaks by XRD analysis when Ni underlayer was electroplated at $10mA/cm^2$ for 2 min, and Pt layer was electroplated at $5mA/cm^2$ for 1 min on the Ni underlayer. Photovoltaic performance and impedance analysis of DSSCs fabricated with this counter electrode shows the highest efficiency of 5.6% and the lowest resistance of 75 ohm.

Electrochemical Characteristics on Methanol Oxidation of Pt-Ru/PPy/Nafion Composite Electrode (Pt-Ru/PPy/Nafion 복합체 전극의 메탄을 산화 특성)

  • Cho Seung-Koo;Park Jong-Ho
    • Journal of the Korean Electrochemical Society
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    • v.7 no.4
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    • pp.201-205
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    • 2004
  • The Pt-Ru electrocatalyst was Prepared on Nafion membrane modified with Polypyrrole by chemical reduction of $H_2PtCI_6\;and\;RuCl_3$ solution ai precursor. From the electron dispersive microanalysis spectroscope(EDS), the Pt-Ru catalyst was located on the surface of Ppy/Nafion composite. The electrochemical oxidation of methanol on Pt-Ru catalyst deposited in Polypyrrole-impregnated Nafion was investigated by cyclic voltammetry (CV) and chronoamperometry. The onset potential of methanol oxidation was shifted to negative potential as the $RuCI_3$ concentration in deposition solution. Also, it was known that the Pt-Ru binary catalyst on Nafion could be directly deposited by using Polypyrrole and resulting Pt-Ru/PPy/Nafion was available for methanol oxidation.

Preparation of Pt/porous Gold Electrode for CO Oxidation (CO 가스 산화를 위한 백금/다공성 골드 전극의 개발)

  • Shin, So-Hyang;Kim, He-Ro;Oh, Cheon-Seok;Ko, Jae-Wook;Kim, Young-Hun
    • Journal of the Korean Institute of Gas
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    • v.15 no.4
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    • pp.27-32
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    • 2011
  • Management of gas safety is becoming important with increasing use of gas facilities. U-safety system is being promoted as part of national management of gas, and thus real-time and in-situ gas sensor should be developed. Detection method for When the gas sensor is installed in gas conduit, explosion may be likely, because hydrocarbon gases is usually used the difference of thermal resistance between reference and working electrode. Therefore, it is required to detect the hydrocarbons, such as $CH_4$ and CO, at room temperature via electrochemically catalytic reaction. In this study, Pt nanoparticle was doped on the porous gold powder by electrolytic plating method, and then it was used as catalytic electrode for CO oxidation. For Pt/PAu electrode, approximately 21% of CO conversion was obtained. It is noted that Pt/PAu electrode could be used to react the oxidation of hydrocarbon gases at room temperature via applying of external voltage.

Degradation of Ferroelectric Properties of Pt/PZT/Pt Capacitors in Hydrogen-containing Environment

  • Kim, Dong-Chun;Lee, Won-Jong
    • Transactions on Electrical and Electronic Materials
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    • v.6 no.5
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    • pp.214-220
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    • 2005
  • The ferroelectric properties of the $Pt/PZT(Pb(Zr,Ti)O_3)/Pt$ capacitors are severely degraded when they are annealed in hydrogen-containing environment. Hydrogen atoms created by the catalytic reaction of Pt top electrode during annealing in hydrogen ambient penetrate into PZT films and generate oxygen vacancies by the reduction of the PZT films, which is likely to cause the degradation. The degree of hydrogen-induced degradation and the direction of voltage shift in P-E curves of the pre-poled PZT capacitors after annealing in hydrogen ambient is dependent on the polarity of the pre-poling voltage. This implies that oxygen vacancies causing hydrogen induced degradation are generated by hydrogen ions having a polarity. The degraded ferroelectricity of the PZT capacitors can be effectively recovered by the shift of oxygen vacancies toward the Pt top electrode interface during post-annealing in oxygen environment with applying negative unipolar stressing.

Study on a Long Term Deactivation of Electro-catalysts in PEMFC for Automobile (자동차용 PEMFC 전극 촉매의 열화 원인에 대한 연구)

  • Chung, Jong-Shik;Chung, Chul-Goo;Kim, Lim;Sung, Yong-Wook
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.63-66
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    • 2006
  • A long term deactivation study was carried out with commercial MEA provided by Hyundai Motor Co. The deactivation phenomena were observed only at high voltage region where there is no diffusion-limited reaction. A rapid deactivation was observed up to 40h owing to the sintering of Pt particles. This was followed a gradual increase in the activity up to 300 h, which is probably caused by improvement in the electrode properties in the presence of current during the reaction. After 300 h, monotonic decrease in the activity was observed owing to dissolution of Pt particles especially in the cathode. The presence oxygen is the cause of oxidation and dissolution of Pt. The dissolution rate can be somewhat retarded by generation of current, which reduces Pt ion back to Pt in the cathode.

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A Study on the Deposition Characteristics of ZnO Piezoelectric Thin film Bulk Acoustic Resonator (FBAR 응용을 위한 ZnO 압전 박막의 증착 특성에 관한 연구)

  • 최승혁;김종성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.8
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    • pp.716-722
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    • 2003
  • ZnO thin films were deposited on Al and Pt electrodes by an RF reactive sputtering system for the fabrication of FBAR (film bulk acoustic wave resonator), and the effect of thermal treatment temperature on their c-axis preferred orientation was investigated. SEM experiments show that columnar structure of ZnO thin films were grown with c-axis normal to electrode material, and XRD experiments show that both ZnO films were grown with (002) plane preferred orientation, but larger diffraction peak was observed with Pt electrode. The peak intensity increased with higher thermal treatment temperature, but c-axis preferred orientation was diminished. The surface roughness of Al thin film was higher than that of Pt, and these affect the surface roughness of ZnO film deposited on the electrode. Though the preferred orientation with respect to Pt(111) plane was improved with higher thermal treatment temperature, this could not improve the c-axis orientation of ZnO film.