• Title/Summary/Keyword: 나피온막

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Effect of elevated air temperature on shell-and-tube Nafion membrane humidifier in PEMFC system (PEMFC시스템의 공기 공급 온도 변화에 따른 중공사형 나피온 막가습기의 성능특성)

  • Yoon, Jae-Eun;Jang, Hyo-sun;Hwang, Jun-Young;Kang, Kyung-Tae
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.345-348
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    • 2009
  • Maintaining proper membrane humidity is crucial to ensure optimal operation of a PEMFC system. A gas-to-gas membrane humidifier is popular technology for external humidification of PEMFC reactant gases. Characteristics of heat and water transfer in shell-and-tube Nafion membrane humidifiers has been experimentally investigated for various dry side inlet temperature of membrane humidifier. The results show that heat flux decreases linearly with dry side inlet temperature of membrane humidifier. The water flux through the membrane varies nonlinearly with the temperature elevation.

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Moisture Absorption Characteristics of Pt/Nafion Membrane for PEMFC Prepared by a Drying Process (건식법에 의해 제조한 PEMFC용 Pt/나피온 막의 흡습 특성)

  • Lee, Jae-Young;Lee, Hong-Ki
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.4
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    • pp.310-315
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    • 2012
  • A simple drying process was developed for the preparation of a Pt/Nafion self-humidifying membrane to be used for a proton-exchange membrane fuel cell (PEMFC). Platinum (II) bis (acetylacetonate), $Pt(acac)_2$ was sublimed, penetrated into the surface of a Nafion film and then reduced to Pt nanoparticles simultaneously without any support of a reducing agent in a glass reactor at $180^{\circ}C$ for 15 min. The process was carried out in $N_2$ atmosphere to prevent the oxidation of Pt nanoparticles at high temperature. The morphology and distribution of the Pt nanoparticles were observed by transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS), and we found that the average Pt particle size was ca. 3.7 nm, the penetration depth was ca. $17{\mu}m$. Almost all Pt nanoparticles were formed just beneath the surface and the number density decreased rapidly as the penetration depth increased. To estimate water absorption characteristics of the Nafion membranes, water uptake at an isothermal condition was measured by dynamic vapor sorption (DVS), and it was found that water uptake of the Pt/Nafion membrane was higher than that of the neat Nafion membrane.