• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.909-912
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• 2000

We synthesized polypyrrole (PPy) nanotubules by oxidative polymerization of the pyrrole monomer within the pores of a polycarbonate template. The electrochemical behavior was investigated using cyclic voltammetry. The redox potential was about -0.5 V vs. Ag/AgCl reference electrode, while the potential was about 0 V for PPy film. It is considered as the backbone grows according to the pore wall. Therefore, it is possible to be arranged regularly. That leads to improvement in the electron hopping. By electrochemical doping of glucose oxidase (GOx) on PPy nanotubules, an enzyme electrode has been fabricated. The kinetic parameter of biochemical reaction with glucose was evaluated. The formal Michaelis constant and maximum current calculated by computer were about 11.4 mmol $dm^3$ and 170.85 A respectively. Obviously, an affinity for the substrate and current response of the PPy nanotubules enzyme electrode are rather good, comparing with that of PPy film.

• 한국표면공학회지
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• 제55권3호
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• pp.173-179
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• 2022

This study presents a roll-to-roll process which is capable of Ag nanowire (AgNW) transfer from polyethylene terephthalate (PET) film to polycarbonate (PC) film. We developed a roll-to-roll machine that consists of two film suppliers, a coater of photo-curable resin, a film laminator, an ultraviolet (UV) exposure unit, and a film winder to facilitate large-area electrode transfer between different flexible substates. Using the process, optimal fabrication condition was investigated by parametric experiments in terms of the UV exposure time, number of thermal cycling, and exposure time of high temperature and humidity. A fabricated AgNW on PC film showed sheet resistance of 52 Ω/sq and optical transmittance of approximately 80 % over a range of visible light.

• 전기화학회지
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• 제15권2호
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• pp.83-89
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• 2012

전기화학적 석출에 의해 Ag-Au 합금층을 전극표면에 형성한 후 진한 질산으로 Ag만을 녹여내는 기법으로 나노다공성 금(nanoporous gold, NPG) 구조를 만들어 전기화학적 산소환원에 대한 촉매현상을 관찰하였다. 석출과정의 전구체의 농도비를 달리하였을 때 나타나는 NPG 표면구조의 변화를 주사전자현미경으로 관찰하고 전기화학적 표면적을 측정하였다. 전기화학적 산소환원 촉매 효율은 NPG 표면의 구조에 따라 달라졌는데, Ag/Au 비율이 2.0에 해당하는 NPG 구조에서 가장 우수한 촉매 현상이 관찰 되었다. 표면구조의 변화에 따른 촉매 활성 변화에서 다공성 구조의 역할이 매우 큰 기여를 하는 반면 표면적의 변화는 큰 영향을 미치지 않았다. 최적 조건의 NPG 구조상의 전기화학적 산소환원 과정의 메커니즘을 회전원판전극 실험을 통해 관찰하였는데, 산성 조건에서 NPG 전극에서 전기화학적 산소환원은 과산화수소를 거쳐 물이 생성되는 2-단계 4-전자 환원 메커니즘으로 진행되었고 염기성 조건에서는 산소가 4개의 전자 전달을 통해 물로 직접적으로 환원 되었다.

• 전기학회논문지
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• 제63권10호
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• pp.1448-1454
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• 2014

In this study, a new type of electrode device is implemented to measure the capacitance energy and interpret it as the ECG (Electrocardiogram) data. The main idea of this new electrode system is to estimate the capacitance on the skin by assembling a capacitive-coupled circuits and translate into the ECG signal. To measure the coupling energy and estimate the aquired data in terms of heart activity, the capacitive-coupled electrode is garmented with fabrics in the form of a chest band or a vest jacket. To compare the ECG data from the capacitive-coupled electrode with the conventional electrode(Ag-AgCl) system, the corelation coefficient between two signals is computed as 0.9517. Thus, we can conclude the fact that capacitive-coupled electrode system can measure a person's heart activity without any contact to his or her skin and can the interpreted as the ECG data.

• 대한화학회지
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• 제25권4호
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• pp.253-262
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• 1981

AgI/PVC${\cdot}$THF막전극은 단일할로겐화이온과 할로겐화이온 혼합물을 질산은표준용액으로 전위차법적정할 때 지시전극으로 사용될 수 있다. 그러나 할로겐화이온혼합물을 단계적정할 때 오차가 매우 큼을 알 수 있었다. 그러나 적정용액에 $NaNO_3$나 $Ba(NO_3)_2$같은 뭉침제를 가하면 오차가 매우 감소한다. 또한 젤라틴과 거름종이의 효과 그리고 온도의 영향도 조사하였다.

• 대한화학회지
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• 제39권1호
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• pp.57-65
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• 1995

$1.0{\times}10^{-2}M\; KNO_3$ 수용액에서 methylene blue(MB)의 전기화학적 환원을 직류 및 펄스차이 폴라로그래피, 순환 전압-전류법, 조절 전위 전기량법으로 조사하였다. MB의 전극환원은 처음 가역파(-0.18 volts vs. Ag/AgCl)에서 2전자 이동의 CE 반응기구로 진행되었다. Methylene blue는 정지된 수은전극에 강하게 흡착되었으며, 조절 전위 전기분해로 환원된 생성물은 공기중에서 빠르게 자동산화되어 본래의 MB로 돌아왔다. pH 변화에 따른 순환 전압-전류 그림과 폴라로그램의 해석을 근거로 하여 CE 반응기구를 제시하였다.

• Nuclear Engineering and Technology
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• 제47권5호
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• pp.579-587
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• 2015

To support the use of nuclear power as a sustainable electric energy generating technology, long-term supply of uranium is very important. The objective of this research is to investigate the use of new adsorbent material for cost effective uranium extraction from seawater. An activated carbon-based adsorbent material is developed and tested through an electrosorption technique in this research. Adsorption of uranium from seawater by activated carbon electrodes was investigated through electrosorption experiments up to 300 minutes by changing positive potentials from +0.2V to +0.8V (vs. Ag/AgCl). Uranium adsorption by the activated carbon electrode developed in this research reached up to 3.4 g-U/kg-adsorbent material, which is comparable with the performance of amidoxime-based adsorbent materials. Electrosorption of uranium ions from seawater was found to be most favorable at +0.4V (vs. Ag/AgCl). The cost of chemicals and materials in the present research was compared with that of the amidoxime-based approach as part of the engineering feasibility examination.

• Bulletin of the Korean Chemical Society
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• 제8권4호
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• pp.225-230
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• 1987

The redox properties of 2-mercaptopyridine N-oxide (mpno) and its oxovanadium complex, $VO (mpno)_2$ have been studied by the use of polarography and cyclic voltammetry. The radical anion of mpno is generated in acetone and is adsorbed to the electrode to form an adsorption wave at -0.21 V vs Ag/AgCl electrode. The normal wave appeared at -0.50 V is attributed to the formation of radical anion. The $VO (mpno)_2$ exhibits one oxidation wave at +0.57 V, and two reduction waves at -1.07 V and -1.76 V vs. Ag/AgCl electrode; the oxidation is fully reversible one-electron process ($VO (mpno)_2\;{\leftrightarrow}\;VO(mpno)_2^+ + e).$ The reduction wave at -1.07 V is quasireversible and is arised from the formation of $VO (mpno)_2^-.$ The second reduction wave at -1.76 V is irreversible and this reduction process consists of two one-electron steps. The sulfur containing ligands seem to enhance the stability of lower oxidation state of vanadium while the oxygen or nitrogen donor of the ligands stabilize the higher oxidation state of vanadium when comparisons are made among several oxovanadium complexes.

• 전자공학회논문지
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• 제50권2호
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• pp.210-220
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• 2013

인구의 고령화 사회에 접어든 최근에는 스마트 의류와 접목된 다양한 형태의 착용형 유헬스 디바이스가 개발되어 일상생활과 가정에서의 생활에 양손을 자유로이 하여 불편함 없이 건강변수 측정이 가능하게 되었다. 하지만 착용형 유헬스 디바이스의 보급과 더불어 이를 응용한 디바이스에 대한 연구 및 개발만이 우선되고 있는 현재, 이에 대한 성능 평가의 중요성에 대한 인식은 미흡한 실정이다. 본 논문에서는 이러한 착용형 유헬스 디바이스와 스마트 의류에 접목하여 전극으로 사용될 수 있는 전도성 섬유를 이용한 전극을 구성하여 심전도(ECG) 신호 측정을 위해 일반적으로 사용되는 패치타입의 Ag-AgCl 전극과 임피던스(Impedance), 심전도(ECG) 신호의 상관관계 비교와 CMRR 측정을 통하여 착용형 유헬스 디바이스에의 사용 가능성을 밝히기 위해 시험을 통한 성능차이를 평가 하였다.

• Journal of the Korean Wood Science and Technology
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• 제50권4호
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• pp.219-236
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• 2022

Wood-based nanocomposite electrode materials were synthesized for application in supercapacitors by mixing nanostructured hematite (Fe₂O₃) with highly porous activated carbon (AC) produced from the wood-waste of Pinus roxburghii. The AC was characterized using various instrumental techniques and the results showed admirable electrochemical properties, such as high surface area and reasonable porosity. Firstly, AC was tested as an electrode material for supercapacitors and it showed a specific capacitance of 59.02 Fg^-1 at a current density of 1 Ag^-1, cycle life of 84.2% after 1,000 cycles (at a current density of 3 Ag^-1), and energy density of 5.1 Wh/kg at a power density of 135 Wkg^-1. However, when the AC was composited with different ratios of Fe₂O₃ (1:1, 2:1, and 1:2), there was an overall improvement in its electrochemical performance. Among the 3 ratios, 2:1 (AC:Fe₂O₃) had the best specific capacitance of 102.42 Fg^-1 at 1 Ag^-1, cycle life of 94.4% capacitance after 1,000 cycles (at a current density of 3 Ag^-1), and energy density of 8.34 Wh/kg at a power density of 395.15 Wkg^-1 in 6 M KOH electrolyte in a 3-electrode experimental setup with a high working voltage of 1.55 V. Furthermore, when Fe₂O₃ was doubled, 1:2 (AC:Fe₂O₃), the electrochemical capacitive performance of the electrode twisted and deteriorated due to either the accumulation of Fe₂O₃ particles within the composite or higher bulk resistance value of pure Fe₂O₃.