• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.735-738
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• 2003

Downsizing electronics requires precision position control with an accuracy of sub-micron order, which demands development of ultra-fine displacive devices. Piezoelectric transducer is one of devices transferring electric field energy into mechanical energy and being capable for fine displacement control. The transducer has been widely used as fine Position control device Multilayer piezoelectric actuator, one of typical piezo-transducer, is fabricated by stacking alternatively ceramic and electrode layers several hundred times followed by cofiring process. Electrode material should be tolerable in the firing process maintaining at ceramic-sintering temperatures up to $1100{\sim}1300^{\circ}C$. Ag-Pd can be used as stable electrode material in heat treatment above $960^{\circ}C$. Besides, adding small quantity ceramic powder allow the actuator to be fabricated in a good shape by diminishing shrinkage difference between ceramic and electrode layers, resulting in avoidance of crack and delamination at and/or nearby interface between ceramic an electrode layers. This study presents synthesis of nano-oxide-added Ag/Pd powders and its feasibility to candidate material tolerable at high temperature. The powders were formed in a co-precipitation process of Ag and Pd in nano-oxide-dispersed solution where Ag and Pd precursors are melted in $HNO_3$ acid.

• 전기화학회지
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• 제10권2호
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• pp.116-125
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• 2007

This article is concerned with synthesis, characterisation and electrochemical application of the mixed conducting perovskite type oxide to electrode materials for solid oxide fuel cell. First, this review provides a comprehensive survey of the various synthetic methods such as solid state reaction, Pechini, glycine nitrate process and sol-gel methods for the preparation of perovskite type oxide powders. Subsequently, the electrical and microstructural properties of the mixed conducting oxides were discussed in detail. Finally, as electrochemical applications of the mixed conducting perovskite type oxides to electrode materials for solid oxide fuel cell, fundamentals of theoretical ac-impedance model for porous mixed conducting electrodes were introduced. Furthermore, the ac-impedance behaviour of porous and dense mixed conducting electrodes prepared by various synthetic methods was discussed.

• 한국수소및신에너지학회논문집
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• 제5권1호
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• pp.41-49
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• 1994

Ti-Bi alloy was prepared by arc melting of appropriate amounts of titanium and bismuth powder. The photocurrent($I_{ph}$) of Ti-Bi oxide electrode was increased with the increase of Bi content, up to 10wt%. The maximum $I_{ph}$ showed $7.6mA/cm^2$ at V=0.5V vs. SCE. The band gap energy of Ti-Bi oxide electrode was observed to 3.0~2.87eV. Surface barrier($V_s$) of Ti-10Bi oxide electrode showed maximum value(1.08V) but didn't exceed 1.23V, then it was impossible to run $H_2$ generation without any other energy sources other than the light. Ti-Bi oxide electrode was found to be quite stable under alkaline solution and showed no signs of photodecomposition.

• 전자공학회논문지A
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• 제32A권7호
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• pp.58-68
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• 1995

Polysilicon capacitors with pyrogenic oxide and TEOX oxide as insulators were fabricated to develop capacitors which can be applied to analog CMOS IC, and the characteristics of the capacitors were compared with each other. The morphology of bottom polysilicon in pyrogenic oxide capacitor is degraded due to the generaged protuberances of the polysilicon grain during oxidataion. The polysilican capacitor with pyrogenic oxide of 57 nm thickness showed that the effective potential barrier height of 0.45 eV is much less than that of MOS capacitor (3.2 eV)when the top electrode is biased with a positive volgate. The morphology of the polysilicon capacitor with TEOS oxide, however, was not degraded during oxide deposition by LPCVD. The polysilicon capacitor with TEOS oxide of 54 nm thickness showed the effective potential barrier height of 1.28 eV when the top electrode is biased with a negative voltage. Therefore, it is concluded that the polysilicon capacitor with TEOS oxide is more applicable to analog CMOS IC than the pyrogenic oxide polysilicon capacitor.

• Bulletin of the Korean Chemical Society
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• 제28권7호
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• pp.1171-1174
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• 2007

We have developed an electrochemical immunosensor that combines the electrocatalytic property of carbon nanotube and the low background current of indium tin oxide (ITO) electrode. A partial monolayer of carboxylated single-walled carbon nanotube (CCNT) is covalently formed on an ITO electrode modified with amine-terminated phosphonic acid. Nonspecifically adsorbed avidin on the hydrophobic sidewalls of CCNT is used to immobilize biotinylated antibody and to reduce the nonspecific binding to CCNT. The biotinylated antimouse IgG bound on avidin and the antimouse IgG conjugated with alkaline phosphatase (ALP) sandwiches a target mouse IgG. ALP catalyzes the conversion of p-aminophenyl phosphate monohydrate into p-aminophenol, which is electrocatalytically oxidized to p-quinone imine on CCNT surface. Moderate electrocatalytic electrode obtained with the combination of CCNT and ITO allows low detection limit (0.1 ng/ mL).

• Journal of Information Display
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• 제8권4호
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• pp.19-22
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• 2007

A new front plate structure of ac-PDP using fence-type aluminum electrode coated with anodic aluminum oxide was investigated. In this structure, ITO and glass dielectric layer were eliminated and expensive Ag BUS electrode was replaced with aluminum. Test panels were prepared using the new structure and their luminance and discharge characteristics were examined. These results indicate that the new structure provide a new way of cost reduction and enhancement of performance of ac-PDPs

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권10호
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• pp.449-452
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• 2005

We fabricated an electrochemical detector (ECD) to catalyze redox reaction efficiently by electrodepositing Prussian blue (PB) on the indium tin oxide (ITO) electrode. Capillary electrophoresis (CE) and amperometric method were used. We investigated the PB surface properties by topography from atomic force microscopy (AFM). Also PB film thickness calibration with respect to deposition time and voltage was used to get better PB surFace. The PB thin film of dense and smooth surface could catalyze redox reaction efficiently. Comparing with CE-ECD microchip using bare-lTO electrode, proposed CE-ECD microchip using PB deposited electrode has shown better sensitivity by determining the detected peak current from the electropherograms while the concentration of tested analyzes was maintained the same. It is verified that detection limit can be lowered for 0.01 mM of dopamine and catechol respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.127-130
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• 2007

A new front plate structure of ac-PDP was explored using fence-type aluminum electrode coated with anodic aluminum oxide.[1] In this structure, ITO and glass dielectric layer were eliminated and expensive Ag BUS electrode was replaced with aluminum. Test panels were prepared using the new structure and their luminance and discharge characteristics were examined. These results indicate that the new structure provide a new way of cost reduction and enhancement of performance of ac-PDPs

• 한국표면공학회지
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• 제52권3호
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• pp.180-185
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• 2019

The demands to improve the performance of the vanadium redox flow battery have attracted an intense research on modifying the carbon-based electrode. In this study, the surface of graphite felt was reformed, using cobalt oxide. The cobalt oxide was implanted into graphite felt during hydrothermal and two step heat treatments. The cobalt was deposited by hydrothermal method and the two step heat treatments made lots of holes on the graphite felt surface which is called as porous surface. The porous surface acts as an electrochemically active site for the cathodic reaction of vanadium redox flow battery. The reformed electrode shows the electrochemically improved performance compared with the pristine electrode.

• 한국자동차공학회논문집
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• 제6권5호
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• pp.10-19
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• 1998

The erosion of electrode in spot welding of aluminium alloy by direct current is dependent on the electric polarity. The positive electrode is much more eroded than the negative one. To explain this phenomenon, Peltier effect has been generally accepted as a unique theory. In this study Peltier effect was evaluated by calculations on the basis of some references and experiments. The difference of heat generated by Peltier effect on both electrode surfaces was, however, only 4% of total heat generated during wel- ding. Because of insufficient explanation, Kohler theory, which is mainly affected by thin oxide film, was introduced. A theoretical calculation showed 17% of the temperature difference between the positive and negative electrode, in case "surface voltage" resulted from oxide film was 30% of total contact voltage. This revealed that the erosion of electrode could be more affected by Kohler theory than effect.an effect.