• 한국전기전자재료학회논문지
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• 제14권5호
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• pp.435-443
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• 2001

As power durable RF SAW filters, AL-(0∼2wt%)Cu alloy multi-layered thin electrodes were deposited on 42° LiTaO$_3$ piezoelectric substrates by magnetron sputtering process, and then ladder-type RF SAW filters, satisfying the electrical specification of CDMA transmission band, were fabricated through optimizing SAW resonator structures. The temperature of film electrodes in SAW filter was increased with RF power, and reached the maxima to cause a failure of SAW filters at the cut-off frequencies of the RF filter band. As RF power increases, the electrodes of Al-Cu alloy showed higher power durability than that of pure Al. The multi-layer laminated film of Al-1wt.% Cu/Cu/Al-1wt%Cu resulted in the best power durability up to 4W of RF power. Every film electrode, however, was destroyed within seconds whenever applying a critical RF power to SAW filters, regardless of the composition and structure of film electrodes. The breakdown of film electrodes under FR power seems to believe due to the fatigue of electrodes caused by repetitive cyclic stress of surface acoustic wave, which is amplified as RF power increases.

• 한국공작기계학회논문집
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• 제16권2호
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• pp.100-105
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• 2007

Electro-rheological(ER) fluid and valve are fabricated and evaluated experimentally in its durability to utilize the hydraulic control systems for long term operation. The two-ports ER valve used in the experiment consist of twelve parallel multi-layer electrodes and provide a restriction to the passage of ER fluid because of the viscous pressure drop and a component induced by the electric field. The durability test of ER valve are performed by measuring the surface roughness of electrodes with variation of an electric field strength and test time(1000 or 1800min.). Also, the shear stress and shear rate are measured to evaluate the durability of ER fluid as function of time. After durability test, ER shear stress increases approximately proportional to the shear rate with applied electric field intensity, In the ER valve, the center line average height roughness(Ra) of copper electrode increases about 1.56 times and ten-point median height roughness(Rz) increases about 2.2 times after the durability test. An understanding of these durability is essential to predicting the service life of ER fluid and valves.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.269-271
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• 2009

We investigated on the sintering behaviors and electrical properties of photo-sensitive aluminum (Al) electrode materials in plasma display panels. General characteristics of Al electrodes was totally different to that of conventional Ag materials; resistivity was decreased with the increasing of metal particle sizes and the amount of frit content and there is almost no width difference between developed and fired electrodes layers. Microstructures of fired electrodes revealed that Al electrodes had different mechanism on necking between metal particles and making electrical conducting path. Chemical durability (especially, antialkalinity) and adhesion of Al electrodes must be carefully controlled. Nevertheless there are difficulties of processing Al electrodes, we developed and optimized photo-sensitive Al materials as address electrodes without any changes of existing patterning equipment and sintering conditions.

• 센서학회지
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• 제33권2호
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• pp.86-92
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• 2024

Flexible electronic devices are exposed to repeated mechanical deformation; therefore, electrode performance is an important element. Recently, a new technology has been developed to improve the adhesion strength between polymer substrates and metal thin films through the cross-linking reaction of bovine serum albumin (BSA) bioconjugation proteins; however, additional performance evaluation as an electrode is necessary. Therefore, in this study, we investigated the effect of adhesive strength between a flexible substrate and a metal thin film on the performance of a flexible electrode. Cracks and changes in the electrical resistance of the electrode surface were observed through outer bending fatigue tests and tensile tests. As a result of a bending fatigue test of 50,000 cycles and a tensile test at 10% strain, the change in the electrical resistance of the flexible electrode with a high adhesion strength was less than 40%, and only a few microcracks were formed on the surface; thus, the electrical performance did not significantly deteriorate. Through this study, the relationship between the adhesion strength and electrical performance was identified. This study will provide useful information for analyzing the performance of flexible electrodes in the commercialization of flexible electronic devices in the future.

• 한국재료학회지
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• 제9권6호
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• pp.622-629
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• 1999

Effects of the fluorination in the $K_2$TiF\ulcorner solution and in-situ KF+ KOH electrolyte on the electrochemical charge-discharge properties of CaNi\ulcorner and the Mg-CaNi\ulcorner electrodes were investigated. In-situ fluorination in the KF+ KOH electrolyte compared with pre-fluorination in the$ K_2$TiF\ulcorner solution could improve the electrochemical cycling durability of CaNi\ulcorner and MG-CaN\ulcorner electrodes. The fluorinated layer on the alloy surface by pre-fluorination to improve the activity and anti-corrosion of the electrodes was dissolved in the pure KOH electrolyte during the cycling. The fluorinated layer was formed continuously on the surface of the electrode by thee2N KF addition in the 6N KOH electrolyte. The excess F\ulcorner ion addition in KOH electrolyte could improve the electrochemical cycling durability of CaNi\ulcorner and Mg-CaNi\ulcorner electrode. But, in case of MG-CaNi\ulcorner electrode, the discharge capacity of the electrode was reduced and the poor cycling property was shown with increasing of the MG process times.

• 한국표면공학회지
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• 제51권4호
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• pp.207-213
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• 2018

Not only efficiency of chlorine evolution reaction (CER) but also durability namely service life is very important property in dimensional stable anode for Ballast Water Management System (BWMS) for marine ships. Many researchers have been focused on improving efficiency of CER by controlling composition, phase and surface area for a long time, but the efforts to increase durability was relatively small. In this study, we have investigated the effect of $TiO_2$ protective interlayers on efficiency and durability of DSA electrodes. $TiO_2$ protective interlayers were prepared by thermal oxidation at 500, 600 and $700^{\circ}C$ on Ti substrate. And then the DSA electrodes consisting of $Ti/RuO_2-PdO-TiO_2$ were prepared by thermal decomposition method on $TiO_2$ interlayers. The efficiencies of CER of DSA electrodes without $TiO_2$ interlayer and with $TiO_2$ interlayer grown at 500, 600 and $700^{\circ}C$ were 94.19, 94.45, 84.60 and 76.75% respectively. On the otherhand, durabilities were 30, 55, 90 and 65 hours respectively. In terms of industrial aspect, the performance of DSA is considered high efficiency and durability which can correspond to total production of chlorine. If we considered the performance index of DSA as the product of efficiency and durability, performance indices could be recalculated as 28.26, 50.85, 76.14 and 49.89 respectively. As the thermal oxidation temperature increasing, life time were increased remarkerbly, while efficiency of CER was decreased slightly. As a result, DSA electrode with $TiO_2$ interlayer grown at $600^{\circ}C$ has shown about 2.7 times performace of original DSA electrode without $TiO_2$ interlayer.

• 한국물환경학회지
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• 제33권1호
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• pp.34-39
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• 2017

Under a corrosive environment, electrodes that are applied in the water-treatment system need not only very high electrochemical activity for fast reactions, but also high durability for cost saving. Therefore, the fabrication condition of iridium electrodes was examined to produce a more durable iridium electrode in this study. Tantalum was selected as a binder to enhance the durability of the iridium electrode. Investigation of the weight ratio between the catalyst and the binder to improve electrochemical activity was performed. Also, to compare the effect of the different coating amounts of the catalyst, the results of CV (Cyclic Voltammetry) and EIS (Electrochemical Impedance Spectroscopy) were discussed. Furthermore, an ALT(Accelerated Lifetime Test) was designed and applied to the electrodes to determine the conditions for highly durable electrode fabrication.

• 융합정보논문지
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• 제12권2호
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• pp.127-133
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• 2022

ITO와 CNT를 적용한 전극을 코팅하여 제작한 대전입자형 전자종이 디스플레이 패널을 제작하여 내구성 및 전기광학적 특성을 비교한다. ITO 전극의 면저항은 10(ohm/sq.)이고 CNT 전극의 면저항은 300, 600, 1000(ohm/sq.)이며 내구성 측정을 위하여 물리적 충격 및 유연성 측정을 진행한다. ITO 전극의 경우 40회의 충격과 10mm의 곡률 반지름에서부터 변화가 시작되나 CNT 전극에서는 변화가 측정되지 않는다. 입자 이동, 반사율 및 응답 시간 측정에 필요한 구동 전압, 전계 등 전기광학 측정결과 CNT 전극은 ITO 전극과 유사한 결과를 얻었다.

• Composites Research
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• 제24권5호
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• pp.17-22
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• 2011

최근 투명전극으로 주로 사용되고 있는 ITO 재료를 대체하가 위해 CNT를 이용한 투명전극의 활용 연구가 활발히 진행되고 있다. 본 연구에서는 건조온도에 따라 CNT와 ITO의 응집이 일어나는 정도가 달라진다는 점을 이용하여 표면을 조절하여 CNT 및 ITO가 코팅된 폴리에틸렌 테레프탈레이트 (PET)를 제조하였다. CNT를 ITO를 대신할 투명전극으로의 활용 가능성을 평가하면서, 표면의 물성 변화를 유도 하기 위해 코팅 후 건조온도를 $20^{\circ}C$, $80^{\circ}C$, 그리고 $120^{\circ}C$ 3단계로 나누어 표면을 관찰하였다. 전기저항측정법을 활용하여 재료의 내구성 및 전기적 물성을 평가함으로써 제조한 투명전극의 특성을 평가하였다. 전자현미경을 이용하여 건조온도에 따른 표면 변화를 관찰하였고, UV-스펙트럼을 통해 건조온도가 증가함에 따라 투과도가 변화하는 것을 확인하였다. 나노입자의 코팅 표면 조절에 따른 전기적 물성 변화를 확인하기 위해 순환전압전류법을 이용 하였다. CNT 코팅 표면의 내구성이 ITO 코팅 표면의 내구성보다 우수함을 알았다. 그리고, 건조온도가 높을수록 나노입자들의 응집이 크게 증가 하여 내구성이 우수한 코팅 표면을 만들며, 이에 따른 전기적 물성의 향상도 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.571-575
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• 2011

Graphite-based electrodes were prepared using synthetic graphite (MCMB 1028) or natural graphite (NG) powder using a dimensionally stable anode (DSA) as a substrate. Their electrochemical properties were investigated in vanadiumbased electrolytes to determine how to increase the durability and improve the energy efficiency of redox flow batteries. Cyclic voltammetry (CV) was performed in the voltage range of -0.7 V to 1.6 V vs. SCE at various scan rates to analyze the vanadium redox reaction. The graphite-based electrodes showed a fast redox reaction and good reversibility in a highly concentrated acidic electrolyte. The increased electrochemical activity of the NG-based electrode for the $V^{4+}/V^{5+}$ redox reaction can be attributed to the increased surface concentration of functional groups from the addition of conductive material that served as a catalyst. Therefore, it is expected that this electrode can be used to increase the power density and energy density of redox flow batteries.