• Title/Summary/Keyword: Cu-electrode

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Process of explosive compaction of internally oxidized powders; Cu-0.15%BeO

  • Moon, J.G.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.447-451
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    • 2002
  • The explosive compaction for processing of electrode material was realized based on axisymmetric loading scheme. The compression of internally oxidized fraction of the alloy Cu-0.15%BeO alloy did not provide a considerable strengthening effect; average microhardness varied from 130 to l50Mpa. The tensile strength comes to 30Mpa. However this method can be applicable to obtain a dense briquette for further extrusion of electrode.

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Fabrication of the Diffusion Barrier for Bus Electrode of Plasma Display by Electroless Ni-B Plating (무전해 Ni-B 도금을 이용한 플라즈마 디스플레이 버스 전극의 확산 방지막 제조)

  • Choi, Jae-Woong;Hong, Seok-Jun;Lee, Hee-Yeol;Kang, Sung-Goon
    • Korean Journal of Materials Research
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    • v.13 no.2
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    • pp.101-105
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    • 2003
  • In this study, we have investigated the availability of the electroless Ni-B plating for a diffusion barrier of the bus electrode. The Ni-B layer of 1$\beta$: thick was electroless deposited on the electroplated Cu bus electrode for AC plasma display. The layer was to encapsulate Cu bus electrode to prevent from its oxidation and to serve as a diffusion barrier against Cu contamination of the transparent dielectric layer in AC plasma display. The microstructure of the as-plated barrier layer was made of an amorphous phase and the structure was converted to crystalline at about 30$0^{\circ}C$. The concentration of boron was about 5∼6 wt.% in the electroless Ni-B deposit regardless of DMAB concentration. The electroless Ni-B deposit was coated on the surface of the electroplated Cu bus electrode uniformly. And the electroless Ni-B plating was found to be an appropriate process to form the diffusion barrier.

Glucose Oxidation on Gold-modified Copper Electrode

  • Lim, Ji-Eun;Ahn, Sang Hyun;Pyo, Sung Gyu;Son, Hyungbin;Jang, Jong Hyun;Kim, Soo-Kil
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2685-2690
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    • 2013
  • The activities of Au-modified Cu electrodes toward glucose oxidation are evaluated according to their fabrication conditions and physico-chemical properties. The Au-modified Cu electrodes are fabricated by the galvanic displacement of Au on a Cu substrate and the characteristics of the Au particles are controlled by adjusting the displacement time. From the glucose oxidation tests, it is found that the Au modified Cu has superior activity to the pure Au or Cu film, which is evidenced by the negative shift in the oxidation potential and enhanced current density during the electrochemical oxidation. Though the activity of the Au nanoparticles is a contributing factor, the enhanced activity of the Au-modified Cu electrode is due to the increased oxidation number of Cu through the electron transfer from Cu to more electronegative Au. The depletion of electron in Cu facilitates the oxidation of glucose. The stability of the Au-modified Cu electrode was also studied by chronoamperometry.

Photoelectrochemical Water Splitting on a Delafossite CuGaO2 Semiconductor Electrode

  • Lee, Myeongsoon;Kim, Don;Yoon, Yong Tae;Kim, Yeong Il
    • Bulletin of the Korean Chemical Society
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    • v.35 no.11
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    • pp.3261-3266
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    • 2014
  • A pellet of polycrystalline $CuGaO_2$ with a delafossite structure was prepared from $Ga_2O_3$ and CuO by high-temperature solid-state synthesis. The $CuGaO_2$ pellet was a p-type semiconductor for which the electrical conductivity, carrier density, carrier mobility and Seebeck coefficient were $5.34{\times}10^{-2}{\Omega}^{-1}cm^{-1}$, $3.5{\times}10^{20}cm^{-3}$, $9.5{\times}10^{-4}cm^2V^{-1}s^{-1}$ at room temperature, and $+360{\mu}V/K$, respectively. It also exhibited two optical transitions at about 2.7 and 3.6 eV. The photoelectrochemical properties of the $CuGaO_2$ pellet electrode were investigated in aqueous electrolyte solutions. The flat-band potential of this electrode, determined using a Mott-Schottky plot, was +0.18 V vs SCE at pH 4.8 and followed the Nernst equation with respect to pH. Under UV light illumination, a cathodic photocurrent developed, and molecular hydrogen simultaneously evolved on the surface of the electrode due to the direct reduction of water without deposition of any metal catalyst.

A study on the $NO_2$ gas detection characteristics of the CuTBP(Copper-tetra-tert-butylphthalocyanine) chemiresistor device (CuTBP(Copper-tetra-tert-butylphthalocyanine) 화학 저항 장치의 $NO_2$ 가스 탐지 특성에 관한 연구)

  • 구자룡;이창희;김태완;김정수
    • Electrical & Electronic Materials
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    • v.10 no.3
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    • pp.233-238
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    • 1997
  • We have investigated gas-detection characteristics of CuTBP (Copper-tetra-tert-butylphthalocyanine) chemiresistor devices exposed to air/200ppm N $O_{2}$ gases. The CuTBP films were made by Langmuir-Blodgett (LB) techniques. Sensitivity, response time, recovery time, and reproducibility of the devices were measured by current voltage characteristics. Interdigital electrode was used to improve the sensitivity. It was observed that a conductance G increases monotonically as the number of interdigital electrode finger pairs increases. As the number of interdigital electrode finger pairs increases, the sensitivity S( $G_{gas}$/ $G_{air}$) increases more than 50 times and stable. But the response time was delayed. The average recovery time of the CuTBP chemiresistor devices turned out to be about 100 second. We have also investigated applicability of the CuTBP chemiresistor device for a gas sensor.sor.

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An Improvement in the Properties of MH Electrode of Ni/MH Battery by the Copper Coating (Ni/MH 전지에서 Cu 도금에 의한 음극활물질의 전극 특성 향상)

  • Cho, Jin Hun;Kim, In Jung;Lee, Yun Sung;Nahm, Kee Suk;Kim, Ki Ju;Lee, Hong Ki
    • Applied Chemistry for Engineering
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    • v.8 no.4
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    • pp.568-574
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    • 1997
  • The effect of microencapsulation of maetal hydride (MH) with copper on the electrode performance of a Ni/MH battery has been investigated. The MH electrodes were prepared with a combination of cold press and paste methods. The discharge capacity of the electrode increased with an addition of small amounts if CMC into the electrode, but decreased when heat-treated in an oxygen-free nitrogen flow. The capacity of a Cu-coated $LaNi_5$ electrode was higher than that of LaNi5electrode. The discharge capacity of the electrode prepared with Cu-coated $LaNi_5$ increased with the increase of copper content in the electrode. It is considered that the increase of copper content enhanced the current density on the electrode surface, leading to the increase of the discharge capacity The MH electrode coated by an acidic electroless plating method showed much higher discharge capacity than that using an alkaline electroless plating method. The discharge capacity of the $LaNi_{4.5}Al_{0.5}$ electrode was higher than that of the $LaNi_5$ electrode. Also, the effect of microencapsulation on the deactivation of $LaNi_5$ was studied using an absorption-desorption cycle in CO-containing hydrogen.

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Development of a New Copper(II) Ion-selective Poly(vinyl chloride) Membrane Electrode Based on 2-Mercaptobenzoxazole

  • Akhond, Morteza;Ghaedi, Mehrorang;Tashkhourian, Javad
    • Bulletin of the Korean Chemical Society
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    • v.26 no.6
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    • pp.882-886
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    • 2005
  • Copper(II) ion-selective PVC membrane electrode based on 2-mercaptobenzoxazole as a new ionophore and o-nitrophenyl octyl ether (o-NPOE) as plasticizer is proposed. This electrode revealed good selectivity for $Cu^{2+}$ over a wide variety of other metal ions. Effects of experimental parameters such as membrane composition, nature and amount of plasticizer, and concentration of internal solution on the potential response of $Cu^{2+}$ sensor were investigated. The electrode exhibits good response for $Cu^{2+}$ in a wide linear range of 5.0 ${\times}$ 10−.6-1.6 ${\times}$ $10^{-2}$ mol/L with a slope of 29.2 ${\pm}$ 2.0 mV/decade. The response time of the sensor is less than 10 s, and the detection limit is 2.0 ${\times}$ $10^{-6}$ mol/L. The electrode response was stable in pH range of 4-6. The lifetime of the electrode was about 2 months. The electrode revealed comparatively good selectivities with respect to many alkali, alkaline earth, and transition metal ions.

Treatment of Wastewater containing Cu and Ni by Electrolysis (전기분해를 이용한 동과 니켈함유 폐수처리)

  • 김재용;이상희
    • Journal of environmental and Sanitary engineering
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    • v.16 no.2
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    • pp.47-55
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    • 2001
  • We investigated to find the optimum operation condition of electrolysis which have an influence on removal efficiency of heavy metals. When we experimented the testing wastewaters containing each 250mg/L of Cu and Ni ions, we got the variables like as pH, amount of electrolyte(NaCl), different species of electrode, electrode gap, electric strength, the number of electrodes, after fastening positive electrode plate with Al, Fe, Ti and negative electrode plate with Stainless Steel plate.

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Nanostructured Metal Organic Framework Modified Glassy Carbon Electrode as a High Efficient Non-Enzymatic Amperometric Sensor for Electrochemical Detection of H2O2

  • Naseri, Maryam;Fotouhi, Lida;Ehsani, Ali
    • Journal of Electrochemical Science and Technology
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    • v.9 no.1
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    • pp.28-36
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    • 2018
  • Metal-organic frameworks have recently been considered very promising modifiers in electrochemical analysis due to their unique characteristics among which tunable pore sizes, crystalline ordered structures, large surface areas and chemical tenability are worth noting. In the present research, $Cu(btec)_{0.5}DMF$ was electrodeposited on the surface of glassy carbon electrode at room temperature under cathodic potential and was initially used as the active materials for the detection of $H_2O_2$. The cyclic voltammogram of $Cu(btec)_{0.5}DMF$ modified GC electrode shows distinct redox peaks potentials at +0.002 and +0.212 V in 0.1 M phosphate buffer solution (pH 6.5) corresponding to $Cu^{(II)}/Cu^{(I)}$ in $Cu(btec)_{0.5}DMF$. Acting as the electrode materials of a non-enzymatic $H_2O_2$ biosensor, the $Cu(btec)_{0.5}DMF$ brings about a promising electrocatalytic performance. The high electrocatalytic activity of the $Cu(btec)_{0.5}DMF$ modified GC electrode is demonstrated by the amperometric response towards $H_2O_2$ reduction with a wide linear range from $5{\mu}M$ to $8000{\mu}M$, a low detection limit of $0.865{\mu}M$, good stability and high selectivity at an applied potential of -0.2 V, which was higher than some $H_2O_2$ biosensors.

DC Magnetron Sputtering of Cr/Cu/Cr Metal Electrodes for AC Plasma Display panel (DC Magnetron Sputtering 법에 의한 AC Plasma Display panel의 Cr/Cu/Cr 금속전극 제조)

  • 남대현;이경우;박종완
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.8
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    • pp.704-710
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    • 2000
  • Metal electrode materials for plasma display panel should have low electrical resistivity in order to maintain stable gas discharge and have fast response time. They should also hae good film uniformity adhesion and thermal stability. In this study Cr/Cu/Cr metal electrode structure is formed by DC magnetron sputtering. Cr and Cu films were deposited on ITO coated glasses with various DC power density and main pressures as the major parameters. After metal electrodes were formed a heat treatment was followed at 55$0^{\circ}C$ for 20 min in a vacuum furnace. The intrinsic stress of the sputtered Cr film passed a tensile stress maximum decreased and then became compressive with further increasing DC power density. Also with increasing the main pressure stress turned from compression to tension. After heat the treatment the electrical resistivity of the sputtered Cu film of 2${\mu}{\textrm}{m}$ in thickness prepared at 1 motor with the applied power density of 3.70 W/cm$^2$was 2.68 $\mu$$\Omega$.cm With increasing the main pressure the DC magnetron sputtered Cu film became more open structure. The heat treatment decreased the surface roughness of the sputtered Cr/Cu/Cr metal electrodes.

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