Performance of phosphonated hydrocarbon ionomer in the fuel cell cathode catalyst layer
Författare
Summary, in English
Inexpensive and environmentally friendly electrolyte polymers that can be operated at higher temperatures and drier conditions are highly interesting for PEM fuel cells for automotive, portable power and stationary electricity generation applications. In this study an ionomer based on polysulfone grafted with poly(vinylphosphonic acid) (PSUgPVPA) in the cathode Pt/C catalyst layer was electrochemically characterized and compared to Nafion. The performance at different levels of humidity at 80◦C was evaluated by polarization measurements, cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The results show that the performance of the PSUgPVPA-based cathode catalyst layer is comparable to that of Nafion at 100% relative humidity (RH) but with some instabilities. However, at drier conditions significant losses of performance for the PSUgPVPA-based cathode was observed. This could be an effect of catalyst poisoning by the ionomer interfering with ORR. However, the concomitant decrease of the electrochemical surface area, double layer capacitance and increased imaginary impedance, indicate that the poorer performance at low humidity is mainly an effect of reduced catalyst wetting by the ionomer in combination with the decreased proton conduction in the ionomeric phase.
Avdelning/ar
Publiceringsår
2013
Språk
Engelska
Sidor
269-277
Publikation/Tidskrift/Serie
Journal of the Electrochemical Society
Volym
160
Issue
3
Länkar
Dokumenttyp
Artikel i tidskrift
Förlag
Electrochemical Society
Ämne
- Chemical Sciences
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 0013-4651