Zirconium phosphate based proton conducting membrane for DMFC application

Abstract

Aproton conducting poly(vinylidene fluoride) (PVDF) supported zirconium phosphate (ZrP) ion-exchange membrane (ZrP/PVDF) was synthesized for potential application in DMFC by f illing the pores of a PVDF film with in-situ grown ZrP particles. Presence of labile protons attached to P]O group was confirmed from 1H NMR and FT-IR characterizations. SEM micrographs showed defect-free top surface. The thermal stability and mechanical strength of the ZrP/PVDF membranewasbetterthan Nafion-117.Watertomethanoluptake ratio was higher while methanol cross-over for ZRP/PVDF membrane was lower than Nafion-117. Membrane possessed fair electrochemical properties; 0.85 static counter-ion transport number, 0.76 meqg 1 ion exchange capacity and 1.25 mScm1 proton conductivity at 30 C. DMFC performance of the synthesized membrane at 35 C was compared with the Nafion-117. DMFCstudieswerealsodoneatdifferent operating conditions and the maximumpeakpowerdensitywas32.3mWcm2at60 C,1Mmethanolconcentrationand 60% relative humidity.