Preparation of Nafion/PTFE/Zr(HPO4)2 composite membranes by direct impregnation method

The viscosities of as received 5.1 wt.% Nafion solutions (EW = 1100, Du Pont Co) blended with various concentrations of ZrOCl₂ were studied. We show the solution viscosity decreases as the wt. ratio of ZrOCl₂]/Nafion] is increased from 0.0 to 0.03, then the viscosity does not change significantly as the wt. ratio of ZrOCl₂]/Nafion] is increased from 0.03 to 0.16, and then the viscosity increases dramatically as the wt. ratio of ZrOCl₂]/Nafion] is increased above 0.16. Four Nafion solutions consisting of 5.1 wt.% Nafion and ZrOCl₂ with ZrOCl₂]/Nafion] wt. ratios of 0.019–0.24 were used with porous poly(tetrafluoroethylene) (PTFE) film to prepare zirconium hydrogenphosphate (ZrP) hybridized Nafion/PTFE (NF–ZrP) composite membranes by direct impregnating porous PTFE in Nafion/ZrOCl₂ solutions. The influence of ZrOCl₂]/Nafion] wt. ratio of Nafion/ZrOCl₂ solution on the membrane morphology of NF–ZrP and polyelectrolyte membrane fuel cell (PEMFC) performance at temperatures of 110–130 °C with relative humidity of 51.7–28.8% RH was investigated.