elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Contact | Deutsch
Fontsize: [-] Text [+]

Influence of Platinum Precipitation on Properties and Degradation of Nafion® Membranes

Helmly, Stefan and Ohnmacht, Benjamin and Hiesgen, Renate and Gülzow, Erich and Friedrich, K. Andreas (2013) Influence of Platinum Precipitation on Properties and Degradation of Nafion® Membranes. ECS Transactions, pp. 969-990. ISSN 1938-5862.

[img] PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
1MB

Abstract

In this study, the role of Pt concentration and distribution in the membrane on ionomer degradation was investigated. Nafion® membranes were impregnated with different mass fraction of Pt via ion-exchange and operated as membrane electrode assemblies (MEAs) at open circuit voltage (OCV). Various MEAs with known Pt concentration were characterized by electrochemical in-situ measurements regarding both, membrane properties and ionomer degradation. Additionally, Pt particle distribution in the membrane cross sections was analyzed. The presence of Pt precipitations was found to influence ionic conductivity and the sensitivity of cell performance for humidification. Ionomer decomposition increased with concentration and surface area of Pt deposits as well as distance between particles. The comparison between Pt precipitated artificially and during operation showed a considerable difference in particle distribution and extent of internal membrane humidification due to water formation at Pt sites.

Document Type:Article
Title:Influence of Platinum Precipitation on Properties and Degradation of Nafion® Membranes
Authors:
AuthorsInstitution or Email of Authors
Helmly, Stefanstefan.helmly@dlr.de
Ohnmacht, Benjaminbenjamin.ohnmachtqdlr.de
Hiesgen, Renaterenate.hiesgen@hs-esslingen.de
Gülzow, Ericherich.guelzow@dlr.de
Friedrich, K. Andreasandreas.friedrich@dlr.de
Date:2013
Journal or Publication Title:ECS Transactions
Refereed publication:Yes
In SCOPUS:No
In ISI Web of Science:No
Page Range:pp. 969-990
ISSN:1938-5862
Status:Published
Keywords:Polymer electrolyte, Fuel cell, Pt catalyst, degradation.
HGF - Research field:Energy
HGF - Program:Efficient Energy Conversion and Use
HGF - Program Themes:Fuel Cells
DLR - Research area:Energy
DLR - Program:E EV - Energy process technology
DLR - Research theme (Project):E - Elektrochemische Prozesse
Location: Stuttgart
Institutes and Institutions:Institute of Technical Thermodynamics > Electrochemical Energy Technology
Deposited By: Dr Daniel Garcia Sanchez
Deposited On:30 Oct 2013 12:00
Last Modified:30 Oct 2013 12:00

Repository Staff Only: item control page

Browse
Search
Help & Contact
Informationen
electronic library is running on EPrints 3.3.12
Copyright © 2008-2012 German Aerospace Center (DLR). All rights reserved.