• 제목/요약/키워드: Electrochemical study

검색결과 2,360건 처리시간 0.037초

Electrochemical Sensing of Hydrogen Peroxide Using Prussian Blue@poly(p-phenylenediamine) Coated Multi-walled Carbon Nanotubes

  • Young-Eun Jeon;Wonhyeong Jang;Gyeong-Geon Lee;Hun-Gi Hong
    • 대한화학회지
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    • 제67권5호
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    • pp.339-347
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    • 2023
  • In this study, a nanocomposite of multi-walled carbon nanotubes@poly(p-phenylenediamine)-Prussian blue (MWCNTs@PpPD-PB) was synthesized and employed for the electrochemical detection of hydrogen peroxide (H2O2). A straightforward approach was utilized to prepare an electrochemical H2O2 sensor using a MWCNTs@PpPD-PB modified glassy carbon electrode, and its electrochemical behavior was investigated through techniques such as electrochemical impedance spectroscopy, cyclic voltammetry, and amperometry. The modified electrode displayed a favorable electrocatalytic response towards the reduction of H2O2 in an acidic solution. The developed sensor exhibited linearity in the concentration range of 0.005 mM to 2.225 mM for H2O2, with high sensitivity (583.6 ㎂ mM-1cm-2) and a low detection limit (0.95 ㎛, S/N = 3) at an applied potential of +0.15 V (vs. Ag/AgCl). Additionally, the sensor demonstrated excellent selectivity, reproducibility, and stability. Moreover, successful detection of H2O2 was achieved in real samples.

Synthesis of Silver Nanoparticles using Pulse Electrolysis in 1-n-butyl-3-methylimidazolium Chloride Ionic Liquid

  • Jeonggeun Jang;Jihee Kim;Churl Kyoung Lee;Kyungjung Kwon
    • Journal of Electrochemical Science and Technology
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    • 제14권1호
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    • pp.15-20
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    • 2023
  • Ionic liquids are considered as a promising, alternative solvent for the electrochemical synthesis of metals because of their high thermal and chemical stability, relatively high ionic conductivity, and wide electrochemical window. In particular, their wide electrochemical window enables the electrodeposition of metals without any side reaction of electrolytes such as hydrogen evolution. The electrodeposition of silver is conducted in 1-n-butyl-3-methylimidazolium chloride ([C4mim]Cl) ionic liquid system with a silver source of AgCl. This study is the first attempt to electrodeposit silver nanoparticles without using co-solvents other than [C4mim]Cl. Pulse electrolysis is employed for the synthesis of silver nanoparticles by varying applied potentials from -3.0 V to -4.5 V (vs. Pt-quasi reference electrode) and pulse duration from 0.1 s to 0.7 s. Accordingly, the silver nanoparticles whose size ranges from 15 nm to ~100 nm are obtained. The successful preparation of silver nanoparticles is demonstrated regardless of the kinds of substrate including aluminum, stainless steel, and carbon paper in the pulse electrolysis. Finally, the antimicrobial property of electrodeposited silver nanoparticles is confirmed by an antimicrobial test using Staphylococcus aureus.

Analysis of electrochemical double-layer capacitors using a Natural Rubber-Zn based polymer electrolyte

  • Nanditha Rajapaksha;Kumudu S. Perera;Kamal P. Vidanapathirana
    • Advances in Energy Research
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    • 제8권1호
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    • pp.41-57
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    • 2022
  • Electrochemical double-layer capacitors (EDLCs) based on solid polymer electrolytes (SPEs) have gained an immense recognition in the present world due to their unique properties. This study is about preparing and characterizing EDLCs using a natural rubber (NR) based SPE with natural graphite (NG) electrodes. NR electrolyte was consisted with 49% methyl grafted natural rubber (MG49) and zinc trifluoromethanesulfonate ((Zn(CF3SO3)2-ZnTF). It was characterized using electrochemical impedance spectroscopy (EIS) test, dc polarization test and linear sweep voltammetry (LSV) test. NG electrodes were made using a slurry of NG and acetone. EIS test, cyclic voltammetry (CV) test and galvanostatic charge discharge (GCD) test have been done to characterize the EDLC. Optimized electrolyte composition with NR: 0.6 ZnTF (weight basis) exhibited a conductivity of 0.6 x 10-4 Scm-1 at room temperature. Conductivity was predominantly due to ions. The electrochemical stability window was found to be from 0.25 V to 2.500 V. Electrolyte was sandwiched between two identical NG electrodes to fabricate an EDLC. Single electrode specific capacitance was about 2.26 Fg-1 whereas the single electrode discharge capacitance was about 1.17 Fg-1. The EDLC with this novel NR-ZnTF based SPE evidences its suitability to be used for different applications with further improvement.

KNiFe(CN)6 전기화학적 이온교환체를 이용한 세슘 양이온의 분리에 관한 연구 (A Study on the Separation of Cesium Cations by Using Electrochemical Ion Exchanger of KNiFe(CN)6)

  • 황영기
    • 전기화학회지
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    • 제15권4호
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    • pp.256-263
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    • 2012
  • 본 연구에서는 전기화학적 이온교환체 중의 하나인 nickel hexacyanoferrate($KNiFe(CN)_6$) 막 전극을 사용하여 세슘 양이온을 분리하는 실험을 수행하였다. 1.0M $NaNO_3$와 1.0M $CsNO_3$의 단일성분계 및 이성분계 수용액에서 순환전위곡선을 측정하여 전극전위, 전류, 전기량의 변화 거동을 조사하였으며, 실험 전과 후에 $KNiFe(CN)_6$ 막의 구조 형태와 원자조성의 변화를 각각 SEM과 EDS 분석을 통하여 조사하였다. 또한 나트륨과 세슘 용액에서 교대로 이온교환 반응을 수행하여 측정한 순환전위곡선과 원자조성으로부터 $KNiFe(CN)_6$의 이온 선택성을 조사하였다. 본 연구의 실험 결과에 의하면, 전기를 인가한 $KNiFe(CN)_6$ 이온교환체는 화학적 유 무기물 이온교환체에 비해 약 40배 이상의 우수한 내구성을 가짐을 알 수 있었다. 또한 $KNiFe(CN)_6$ 이온교환체는 나트륨보다 세슘에 대해 보다 높은 선택도를 가짐을 확인할 수 있었다.

소규모 오수처리를 위한 전기화학적 방법에 의한 대장균 소독에 관한 연구 (A Study on Escherichia Coli Disinfection by the Electrochemical Method for Small Sewerage System)

  • 박영식;정노성;김동석
    • 한국환경과학회지
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    • 제16권4호
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    • pp.441-447
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    • 2007
  • This study was carried out to investigate the effect of electrochemical (EC) disinfection of artificial wastewater contaminated by Escherichia coli culture. Circulated batch type electrochemical disinfection system using three plates electrodes was used. Also, the several factors (pH, ORP, DO, temperature, current, conductivity) were measured in order to investigate the fundamental design factor in the EC disinfection system. It was demonstrated that the EC process was highly effective for wastewater disinfection. At the constant voltage, the disinfection efficiency was increased according to time. The disinfection efficiency and current increased as the increase of voltage. The variation of conductivity was a little related to the variation of CFU (colony forming units). The differences in disinfection efficiency according to the ice pack and the variation of electrodes were not occurred. The EC disinfection efficiency and current increased according to the increase of circulating flow rate.

내부개질형 고체산화물 연료전지의 마이크로 전극구조가 성능에 미치는 영향에 관한 해석적 연구 (A Simulation Study of the Effect of Microstructural Design on the Performance of Solid Oxide Fuel Cells With Direct Internal Reforming)

  • 손상호;남진현
    • 한국수소및신에너지학회논문집
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    • 제24권5호
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    • pp.401-412
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    • 2013
  • The paper is to study on the simulation of the micro/macroscale thermo-electrochemical model of a single cell of anode-supported SOFC with direct internal reforming. The coupled heat and mass transport, electrochemical and reforming reactions, and fluid flow were simultaneously simulated based on mass, energy, charge conservation. The micro/macroscale model first calculates the detailed electrochemical and direct internal reforming processes in porous electrodes based on the comprehensive microscale model and then solve the macroscale processes such as heat and mass transport, and fluid flow in SOFCs with assumption of fully-developed flow in gas channel. The simulation results evaluate the overall performance by analyzing distributions of mole fraction, current density, temperature and microstructural design in co/counter flow configurations.