http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Developement of a PEFC electrodes under the high temperature and low humidified conditions
류성관(Ryu, Sung-Kwan),최영우(Choi, Young-Woo),박진수(Park, Jin-Soo),임성대(Yim, Sung-Dae),양태현(Yang, Tae-Hyun),김한성(Kim, Han-Sung),김창수(Kim, Chang-Soo) 한국신재생에너지학회 2009 한국신재생에너지학회 학술대회논문집 Vol.2009 No.11
Generally, Nafion ionomer is used in the polymer electrolyte fuel cell (PEFC) electrodes to achieve high power density. At the high temperature operation of PEFC, however, ionic conductivity of Nafion remarkably decreased due to the evaporation of water in Nafion polymer. Recently, many researchers have focused on using the Ionic Liquids(ILs) instead of water in Nafion polymer. ILs have intrinsic properties such as good electrochemical stability, high ionic conductivity, and non-flammability. Especially, ILs play a crucial role in proton conduction by the Grottuss mechanism and act as water in water-free Nafion polymer. However, it was found that the ILs was leached out of the polymer matrix easily. In this study, we prepared membrane electrode assemblies with various contents of ILs. The effect of ILs in the electrode of each designed was investigated by a cyclic voltammetry measurement and the cell performance obtained through a single cell test using H2/Air gases. Electrodes with different contents of ILs in catalyst layer were examined at high temperature and low humidified condition.
류성관(Ryu, Sung-Kwan),박진수(Park, Jin-Soo),양태현(Yang, Tae-Hyun),박승희(Park, Seung-Hee),박석희(Park, S.H.),윤영기(Yoon, Y.G.),김한성(Kim, Han-Sung),김창수(Kim, Chang-Soo) 한국신재생에너지학회 2009 한국신재생에너지학회 학술대회논문집 Vol.2009 No.06
In this study, we prepared electrodes containing ionic liquid for high temperature polymer electrolyte fuel cells. Effects of ILs on electrochemical properties of the electrodes were investigated carrying out measurement of cyclic voltammograms of the various electrodes with the content of IL in a strong supporting electrolyte. As the ILs content increased in electrodes, electrochemical surface area(ESA) decreased due to the leakage of ILs from Nafion ionomer. In addition, two case of cyclic voltammograms under two simulated environment, i.e. IL leakage from Nafion ionomer in I) electrode and ii) polymer electrolyte, were investigated. As a result, IL leakage from polymer electrolyte showed worse results in electrochemical properties of the electrode.
류성관(Ryu, Sung Kwan),최영우(Choi, Young Woo),양태현(Yang, Tae Hyun),임성대(Yim, Sung Dae),김한성(Kim, Han Sung),김창수(Kim, Chang Soo) 한국신재생에너지학회 2010 한국신재생에너지학회 학술대회논문집 Vol.2010 No.11
Polymer electrolyte fuel cells (PEFCs) have received a lot of attention as a power source for both stationary and mobile applications due to their attractive feature. In general, the performance of PEFCs is highly affected by the property of the electrodes. A PEFC electrode essentially consists of a gas diffusion layer and a catalyst layer. The gas difusion layer is highly porous and hydrophobicized with PTFE polymer. The catalyst layer usually contains electrocatalyst, proton conducting polymer, even PTFE as additive. Particularly, the proton conducting ionomer helps to increase the catalytic activity at three-phase boundary and catalyst utilization. Futhermore, it helps to retain moisture, resulting in preventing the electrodes from membrane dehydration. The most widely used proton conducting ionomer is perfluorinated sulfonic acid polymer, namely, Nafion from DuPont due to its high proton conductivity and good mechanical property. However, there are great demands for alternative ionomers based on non-fluorinated materials in terms of high temperature availability, environmental adaptability and production cost. In this study, the electrodes with the various content of the sulfonated poly(ether sulfone) ionomer in the catalyst layer were prepared. In addition, we evaluated electrochemical properties of the prepared electrodes containing the various amount of the ionomers by using the cyclic voltammetry and impedance spectroscopy to find an optimal ionomer composition in the catalyst layer.