• 제목/요약/키워드: Electrochemical cell

검색결과 1,542건 처리시간 0.03초

직접탄소 연료전지에서 RDF 및 RPF의 전기화학반응 특성에 관한 실험적 연구 (An Experimental Study on the Characteristics of Electrochemical Reactions of RDF/RPF in the Direct Carbon Fuel Cell)

  • 안성율;이영훈;엄성용;성연모;문철언;강기중;최경민;김덕줄
    • 한국수소및신에너지학회논문집
    • /
    • 제23권5호
    • /
    • pp.513-520
    • /
    • 2012
  • The electrochemical reaction of refuse derived fuel (RDF) and refuse plastic/paper fuel (RPF) was investigated in the direct carbon fuel cell (DCFC) system. The open circuit voltage (OCV) of RPF was higher than RDF and other coals because of its thermal reactive characteristic under carbon dioxide. The thermal reactivity of fuels was investigated by thermogravimetric analysis method. and the reaction rate of RPF was higher than other fuels. The behavior of all sample's potential was analogous in the beginning region of electrochemical reactions due to similar functional groups on the surface of fuels analyzed by X-ray Photoelectron Spectroscopy experiments. The potential level of RDF and RPF decreased rapidly comparing to coals in the next of the electrochemical reaction because the surface area and pore volume investigated by nitrogen gas adsorption tests were smaller than coals. This characteristic signifies the contact surface between electrolyte and fuel is restricted. The potential of fuels was maintained to the high current density region over 40 $mA/cm^2$ by total carbon component. The maximum power density of RDF and RPF reached up to 45~70% comparing to coal. The obvious improvement of maximum power density by increasing operating temperature was observed in both refuse fuels.

Direct Microwave Sintering of Poorly Coupled Ceramics in Electrochemical Devices

  • Amiri, Taghi;Etsell, Thomas H.;Sarkar, Partha
    • Journal of Electrochemical Science and Technology
    • /
    • 제13권3호
    • /
    • pp.390-397
    • /
    • 2022
  • The use of microwaves as the energy source for synthesis and sintering of ceramics offers substantial advantages compared to conventional gas-fired and electric resistance furnaces. Benefits include much shorter processing times and reaching the sintering temperature more quickly, resulting in superior final product quality. Most oxide ceramics poorly interact with microwave irradiation at low temperatures; thus, a more complex setup including a susceptor is needed, which makes the whole process very complicated. This investigation pursued a new approach, which enabled us to use microwave irradiation directly in poorly coupled oxides. In many solid-state electrochemical devices, the support is either metal or can be reduced to metal. Metal powders in the support can act as an internal susceptor and heat the entire cell. Then sufficient interaction of microwave irradiation and ceramic material can occur as the sample temperature increases. This microwave heating and exothermic reaction of oxidation of the support can sinter the ceramic very efficiently without any external susceptor. In this study, yttria stabilized zirconia (YSZ) and a Ni-YSZ cermet support were used as an example. The cermet was used as the support, and a YSZ electrolyte was coated and sintered directly using microwave irradiation without the use of any susceptor. The results were compared to a similar cell prepared using a conventional electric furnace. The leakage test and full cell power measurement results revealed a fully leak-free electrolyte. Scanning electron microscopy and density measurements show that microwave sintered samples have lower open porosity in the electrode support than conventional heat treatment. This technique offers an efficient way to directly use microwave irradiation to sinter thin film ceramics without a susceptor.

활성탄소 전극의 제조공정에 따른 EDLC의 전기화학적 특성 (Electrochemical Characteristics of EDLC Fabricated by Different Preparation Processes of Activated Carbon Electrode)

  • 양천모;김현중;조원일;조병원;윤경석;임병오
    • 전기화학회지
    • /
    • 제4권3호
    • /
    • pp.98-103
    • /
    • 2001
  • EDLC(electric double layer capacitor)용 활성탄소전극의 제조공정을 dip coating method, doctor blade coating method, paste rolling method로 달리하여 전기화학적 특성과 비축전 용량을 조사하였다. Dip coating method에 의한 전극제조시 전해질염으로 LiPF6를 이용하고 유기용매로 PC-DEC를 이용한 EDLC의 비축전 용량이 130F/g으로 가장 우수하였고, 선형의 시간전압곡선에서의 IR-drop도 0.11V로 작았으며 CV(cyclic voltammetry) 분석 또한 이상적인 EDLC의 특성을 나타내었다.

유체 전산모사를 통한 직접 메탄올 연료전지의 시뮬레이션 (Simulation of Direct Methanol Fuel Cells Employing Computational Fluid Dynamics(CFD))

  • 김영진;이태희;오인환;홍성안;김혁년;하흥용
    • 전기화학회지
    • /
    • 제6권1호
    • /
    • pp.28-35
    • /
    • 2003
  • 상용 유체 전산모사 코드인 FLUENT ver.6.0을 이용하여 직접 메탄을 연료전지의 전기화학적 해석 및 유로 내에서의 유체의 유동특성을 분석하였다 본 전산모사를 통해 유로 내의 유속, 압력, 온도, 농도 및 전류밀도 분포에 대한 다양한 정보를 얻을 수 있었으며, 유로 디자인에 따른 반응물 및 생성물의 유동에 대한 정보로부터 최적의 유로 형태를 결정할 수 있었다. 이와 같은 전산모사 방법을 사용하면 직접 메탄을 연료전지의 전극과 분리판 유로의 구조를 최적화하는데 매우 유리하다.

나노복합 태양전지를 위한 CdTe 전착 거동의 순환전류법을 이용한 전기화학적 분석 (Electrochemical Analysis of CdTe Deposition Using Cyclovoltammetric Method for Hybrid Solar Cell Application)

  • 김성훈;한원근;진홍성;이재호
    • 한국표면공학회지
    • /
    • 제42권5호
    • /
    • pp.197-202
    • /
    • 2009
  • The electrodeposition in acidic aqueous electrolyte bath of cadmium telluride on gold electrodes has been studied by electrochemical analysis. Conventional cyclic voltammetry using potentiostat is considered as a reliable method to study electrochemical behavior of electrodeposition of CdTe. In this paper, the mechanism of CdTe deposition and its cyclic voltammetry were studied with the Te ion concentration, temperature, potential, and scan rate. We also investigated surface morphologies using FESEM and atomic composition of Cd and Te using EDS. Atomic composition of Cd and Te were varied with Te ion concentration in the electrolyte.

A Non-Pt Catalyst for Improved Oxygen Reduction Reaction in Microbial Fuel Cells

  • Kim, Jy-Yeon;Han, Sang-Beom;Oh, Sang-Eun;Park, Kyung-Won
    • 전기화학회지
    • /
    • 제14권2호
    • /
    • pp.71-76
    • /
    • 2011
  • Fe-tetramethoxyphenylporphyrin on carbon black (Fe-TMPP/C) is examined and compared with carbon (C) and Pt-coated carbon (Pt/C) for oxygen reduction reaction in a two chambered microbial fuel cell (MFC). The Fe-TMPP/C is prepared by heat treatment and characterized using SEM, TEM, and XPS. The electrochemical properties of catalysts are characterized by voltammerty and single cell measurements. It is found that the power generation in the MFC with Fe-TMPP/C as the cathode is higher than that with Pt/C. The maximum power of the Fe-TMPP/C is 0.12 mW compared with 0.10 mW (Pt/C) and 0.02 mW (C). This high output with the Fe-TMPP/C indicates that MFCs are promising in further practical applications with low cost macrocycles catalysts.

고체산화물연료전지의 시뮬레이션을 위한 전기화학모델 (Electrochemical model for the simulation of solid oxide fuel cells)

  • 박준근;이신구;배중면
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
    • /
    • pp.63-66
    • /
    • 2008
  • This study presents 0-dimensional model for solid oxide fuel cells(SOFCs). The physics of the cell and the simplifying assumptions are presented, and only hydrogen participates in the electrochemical reaction. The electrical potential is predicted using this model. The Butler-Volmer equation is used to describe the activation polarization and the exchange current density is changed according to the partial pressure of reactants and the temperature. The electrical conductivities of electrodes and an electrolyte are calculated for the ohmic polarization. Material characteristics and temperature affect those factors. Analysis of concentration polarization based on transport of gaseous species through porous electrodes is incorporated in this model. Both binary diffusion and Knudsen diffusion are considered as the diffusion mechanism. For validation, simulation results at this work are compared with our experimental results and numerical results by other researchers.

  • PDF