Preparation and properties of novel sulfonated poly(p-phenylene-co-aryl ether ketone)s for polymer electrolyte fuel cell applications

Abstract A series of sulfonated poly( p -phenylene- co -aryl ether ketone) (SPP- co -PAEK) membranes are successfully prepared from 2,5-dichloro-3′-sulfobenzophenone and 2,2′-bis[4-(4-chlorobenzoyl)] phenoxyl perfluoropropane through Ni(0)-catalyzed copolymerization for polymer electrolyte membrane fuel cell (PEFC) applications. The obtained SPP- co -PAEKs have fairly high reduced viscosities and give ductile and transparent membranes with good mechanical strength. All the membranes exhibit comparable or even better proton conductivities than that of Nafion 112 in the full hydrate state. In addition, the membranes showed almost isotropic proton conductive behavior with σ ⊥ / σ || values in the range of 0.85–0.92. Fuel cell operation using SPP- co -PAEK(3/1) (IEC = 2.0 meq g −1 , thickness of 38 μm, feed gases: H 2 /air) exhibited rather good performances: open circuit voltage of 0.94 V, cell voltage at 1.0 A cm −2 of 0.61 V, and output at 1.7 A cm −2 of 0.85 W cm −2 under 90 °C and 82/68% relative humidity condition. The results suggested that these SPP- co -PAEK membranes are promising candidates for PEFC applications.