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Magnetismus Poster: Do., 13:00–15:30 D-P214
Characterisation of Polymer Membranes for Fuel Cell applications using
Synchrotron Radiation
Volker Abetz 1 , Suzana Pereira Nunes 1 , Mariela Leticia Ponce 1 , Dominique
Gomes 1 , Günter Goerigk 2 , Sergio Funari 2 , Jerusa Roeder Jesus 1
1 GKSS Forschungszentrum, Max Planck Str., D 21502 Geesthacht, Germany –
2 Hasylab DESY, Notkerstraße 85, D-22067, Hamburg, Germany
The major disadvantages of Perfluorinated polymers in polymer electrolyte fuel cells
(PEFCS), are their low proton conductivity over 100 ◦ C as well as their high cost.
Polymers containing heterocyclic rings with basic character have been shown to be
quite interesting for PEFCs application, since their ability to transport protons above
100 ◦ C [1, 2]. The presence of pyridine-like N sites may favour additional points for
proton jumps, contributing to the proton conductivity. Previous ASAXS, WAXS and
SAXS studies were performed on materials like sulfonated polymer matrix containing
inorganic components (heteropolyacids, zirconium phosphates, sulfonated silica particles
and zirconium oxides), to evaluate structural parameters like particles distribution,
size and crystallinity for a better understanding of the correlation between structural
and proton conducting properties of them. Detailed microstructure studies by SAXS
and ASAXS have been done for fuel cell membrane materials based on:
1. Poly(ether ether ketones), polyoxadiazoles (POD) and polytriazoles (PT): effect
of degree of sulfonation and distribution of sulfonic groups, on the channels
structure between the hydrophobic and hydrophilic phases. The study was accompanied
by proton conductivity measurements. High ionic conductivity values
were obtained (order of magnitude of 10 −3 S cm −1 at 50 ◦ C) for low sulfonated
POD and PT. This result may be attributed to the presence of pyridinelike N
sites [1].
2. Nanocomposites: The previous work was continued including the use of metalorganic
frameworks with a variety of functionalities on the surface of the pores
or with guest molecules (e. g. conductive acids) and the use of sulfonated silica
particles.
[1] R.F. Savinelli et al., US Patent 5,525,436 (1996)
[2] D. Gomes et al., J. Polym. Sci. Part B, in press
[3] R.F. Savinelli et al., US Patent 5,525,436 (1996)
[4] D. Gomes et al., J. Polym. Sci. Part B, in press