Journal of Membrane Science & Technology

Proton exchange membrane for fuel cell operation: Consequence of foreign cations

2^nd International Conference on Membrane Science and Technology

September 13-14, 2018 | London, UK

BAS Corine

Universite Savoie Mont Blanc, France

Keynote: J Membr Sci Technol

Abstract:

The proton exchange membranes such as perfluorosulfonic acid ionomer (PFSA) are used as electrolytes in low temperature fuel cell. When cationic impurities are present in the polymer electrolyte membrane, the performance of fuel cell can be significantly reduced due to the conductivity decrease. At the same time, the presence of cations within the ionomer impacts the mechanical behaviour of the membrane. No impact on the energy necessary to initiate cracks in the membrane was measured, but cationic contaminants strongly emphasize their propagation. A sharp change in the thermal behaviour was evidenced at a given threshold and also is controlled by the Lewis acid strength (LAS) of the cations. These results were correlated to vibrational changes, especially to the polar groups as revealed by infrared spectroscopy. For example, a stepwise behaviour of the symmetrical stretching band at 970 cm-1 appears correlated to the evolution of drop modulus temperature determined by dynamic mechanical analysis. In addition, an estimation of the amount of contaminants and their identification was made possible through the relative intensity of the bending vibration of the hydronium, while the identification of cations may be confirmed with the wavenumbers of lateral group vibrations. These calibration curves were applied to analyze long side chain (LSC) and short side chain (SSC) PFSA membranes after fuel cell operation. Cations within the membrane after fuel cell operation originate from the degradation of the radical scavenger. Recent Publications 1. De Moor G, Bas C, Charvin N, Dillet J, Maranzana G, et al. (2016) Perfluorosulfonic acid membrane degradation in the hydrogen inlet region: A macroscopic approach. International Journal of Hydrogen Energy 41(1):483???496. 2. Moukheiber E, Bas C and Flandin L (2014) Understanding the formation of pinholes in PFSA membranes with the essential work of fracture (EWF). Int. J. Hydrogen Energy 39(6): 2717???2723. 3. Dubau L, Castanheir A L, Maillard F, Chatenet M, Lottin O, et al. (2014) A review of PEM fuel cell durability: materials degradation, local heterogeneities of aging and possible mitigation strategies. Wiley Interdisciplinary Reviews: Energy and Environment 3(6):540???560. 4. Moukheiber E, Bas C, Alberola N D and Flandin L (2013) Infrared and thermal behaviour of proton exchange membrane (PEM) after cationic contamination. J. Memb. Sci., 431:105???112. 5. Bas C, Alb�rola N D and Flandin L (2010) Effects of contaminant on thermal properties in perfluorinated sulfonic acid membranes. J. Memb. Sci. 363:67???71.

Biography :

BAS Corine is Professor of Polymer Science at the University Savoie Mont Blanc. She worked on the characterization of polymer membrane to determine microstructural probe for gas separation, in particular based on positron annihilation spectroscopy. Now, her research mainly focuses on the degradation characterization of proton exchange membranes for fuel cell applications to improve their durability.

E-mail: corine.bas@univ-smb.fr