• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.196-197
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• 2015

ZnSe의 전기화학적 거동은 각각 다른 pH를 갖는 전해질에서의 linear sweep voltammogram 분석에 의해 체계적으로 고찰되었다. 제어된 조성을 갖는 칼코지나이드 ZnSe 박막이 complexing agent의 역할을 하는 citrate를 포함한 알카리 용액에서 전해 증착되었다. 다른 pH의 전해질에서 증착된 ZnSe 박막의 형상을 분석하고, 추가적으로 다른 pH의 전해질 및 어닐링 온도 변화에 따른 ZnSe 박막의 XRD분석이 이루어졌다.

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.155-157
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• 2011

본 논문에서는 In-situ 전기화학 AFM과 In-situ 전기화학 Raman을 주된 분석방법으로 리튬 이차전지의 흑연 음극과 PC계 전해질 계면에서의 반응을 이해하고자 하였다. In-situ 전기화학 AFM 분석방법을 통하여 PC계 전해질에서 용매화된 리튬의 삽입/탈리반응이 진행되는 것을 확인할 수 있었으며 In-situ 전기화학 Raman 분석방법을 이용하여 PC계 전해질에서는 삼원계 Li-GIC가 생성되는 것을 확인할 수 있었다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.88.2-88.2
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• 2011

본 연구는 아연/공기전지 설계기술 개발을 위한 기초 연구로서 전산해석을 이용하여 전해질 유동에 따른 아연/공기전지의 성능 예측에 관한 것이다. 전산해석모델은 전기화학 방정식과 유체유동 방정식으로 구성하였으며, 화학종 반응에 관한 지배방정식으로는 Nernst-Planck식을 이용하였고 전극표면의 전기화학반응은 Butler-Volmer식을 이용하였다. 또한 유체유동 방정식은 Navier-Stoke식을 적용하여 전해질 유동에 따른 전기화학적 성능 변화를 모사하였다. 아연/공기전지 성능 평가 실험으로부터 얻은 I-V 곡선과 전산해석결과와의 비교/분석을 통하여 전기화학모델의 타당성을 검증하였으며, 유체 유동 방정식과의 연동해석을 적용하여 전해질 유입 위치 및 유입 속도에 따른 아연/공기전지의 성능 변화를 조사하였다. 아연/공기전지의 성능은 전해질 유입 위치가 아연극에 가까울수록, 유입 속도가 빠를수록 향상되는 것을 확인할 수 있었다.

• Journal of Sensor Science and Technology
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• v.6 no.4
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• pp.307-315
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• 1997

In this paper, a sample chamber which provide easy replacement of ISFET sensor and consume only small sample volume for electrolyte analysis is designed and a 4-channel electrolyte analyzer employing 2-point calibration method is implemented. In addition, we proposed sample loading detection circuit for minimizing sample and calibration solutions and implemented it. Developed electrolyte analyzer consists of control system part and flow system part. For the effective control of the developed hardware, system software is developed as three individual routines ; measuring routine, calibration routine and washing routine.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.241-251
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• 2014

This study was carried out to develop a simple, rapid and reliable assessment model to predict cold tolerance in Pittosporum tobira, a broad-leaved evergreen commonly used in the southern region of South Korea, which can minimize the possible experimental errors appeared in a electrolyte leakage test for cold tolerance assessment. The modeling procedure comprised of regrowth test and a electrolyte leakage test on the plants exposed to low temperature treatments. The lethal temperatures estimated from the methodological combinations of a electrolyte leakage test including tissue sampling, temperature treatment for potential electrical conductivity, and statistical analysis were compared to the results of the regrowth test. The highest temperature showing the survival rate lower than 50% obtained from the regrowth test was $-10^{\circ}C$ and the lethal was $-10^{\circ}C{\sim}-5^{\circ}C$. Based on the results of the regrowth test, several methodological combinations of electrolyte leakage tests were evaluated and the electrolyte leakage lethal temperatures estimated using leaf sample tissue and freeze-killing method were closest to the regrowth lethal temperature. Evaluating statistical analysis models, linear interpolation had a higher tendency to overestimate the cold tolerance than non-linear regression. Consequently, the optimal model for cold tolerance assessment of P. tobira is composed of evaluating electrolyte leakage from leaf sample tissue applying freeze-killing method for potential electrical conductivity and predicting lethal temperature through non-linear regression analysis.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.117-123
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• 2021

The effects of electrolyte concentration on the electrochemical properties of Fe4[Fe(CN6)]3(FeHCF) as a novel active material for the electrode of aqueous zinc-ion batteries was investigated. The electrochemical reactions and structural stability of the FeHCF electrode were significantly affected by the electrolyte concentration. In the electrolyte solutions of 1.0-7.0 mol dm-3, the charge-discharge capacities increased with increasing electrolyte concentration, however gradually decreased as the cycle progressed. On the other hand, in the 9.0 mol dm-3 electrolyte solution, the initial capacity was relatively small, however showed good cyclability. Additionally, the FeHCF electrode after five cycles in the former electrolyte solutions, had a change in crystal structure, whereas there was no change in the latter electrolyte solution. This suggests that the performance of the FeHCF electrode is greatly influenced by the hydration structure of zinc ions present in electrolyte solutions.

• 기계와재료
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• v.23 no.2
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• pp.68-79
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• 2011

전고체 리튬 이차전지는 기존 리튬 이차전지의 구성요소 가운데 액체 전해질을 고체 전해질로 대체한 것을 말한다. 전지의 폭발이나 화재의 위험성이 업소 제조공정이 단순화되며 고 에너지 밀도화 가능성에서 기존 리튬 이차전지보다 유리한 전고체 리튬이차전지는 차세대 이차전지로 주목받고 있다. 본고에서는 전고체 리튬 이차전지의 핵심 요소기술인 세라믹 고체 전해질과 용량 및 에너지 밀도 향상을 위한 전고체 이차전지 구조 등에 대해 연구개발 현황을 조사하였다.

• Journal of the Korean Electrochemical Society
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• v.19 no.2
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• pp.45-49
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• 2016

In order to mitigate oxidative degradation of polymer membrane during fuel cell operation, an organic radical quencher was introduced. Rutin was selected as a radical quencher and mixed with sulfonated poly(arylene ether sulfone) to prepare composite membrane. Physicochemical properties of the composite membranes such as water uptake and proton conductivity were characterized. Hydrogen peroxide exposure experiment, which can mimic accelerated oxidative stability test during fuel cell operation, was adopted to evaluate the oxidative stability of the membranes. The composite membranes containing Rutin showed similar proton conductivity and enhanced oxidative stability compared to pristine ones.

• Journal of the Korean Electrochemical Society
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• v.23 no.4
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• pp.81-89
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• 2020

To understand the performance of the electrochemical device, the analysis of the mechanism of ionic conduction is important. However, due to the ionic interaction in the electrolyte and the complexity of the electrolyte structure, a clear analysis method of the ion conduction mechanism has not been proposed. Instead, a variety of mathematical models have been devised to explain the mechanism of ion conduction, and this review introduces the Arrhenius and Vogel-Tammann-Fulcher (VTF) model. In general, the above two mathematical models are used to describe the temperature dependence of the transport properties of electrolytes such as ionic conductivity, diffusion coefficient, and viscosity, and a suitable model can be determined through the linearity of the graph consisting of the logarithm of the moving property and the reciprocal of the temperature. Currently, many electrolyte studies are evaluating the suitability of the above two models for electrolytes by varying the composition and temperature range, and the ion conduction mechanism analysis and activation energy calculation are in progress. However, since there are no models that can accurately describe the transport properties of electrolytes, new models and improvement of existing models are needed.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.93-105
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• 2012

Activity coefficients and solubilities of L-Valine and L-Proline in aqueous solutions containing each of four electrolytes such as NaCl, KCl, $NaNO_3$ and $KNO_3$ were measured at 298.15 K. The measurements of activity coefficients were carried out in the electrochemical cell coupled with two ion-selective electrodes (cation and anion), and the solubilities were measured by the gravimetric analysis of saturated solutions in equilibrium with the solid phase of amino acid. The measured activity coefficients of electrolytes and amino acids were correlated with the theoretical thermodynamic model presented in the previous work [Korean Chem. Eng. Res. 48(4), 519(2010)]. It was found that the activity coefficients of amino acids and electrolytes described based on the our previous model were well agreeable with experimental data. Also the experimental solubility data of L-Valine and L-Proline were successfully correlated with the thermodynamic relation mentioned in the previous work.