(268a) Nanoscale Investigation of Morphologies in Polymer Electrolyte/Pvdf Blend Membranes

The polymer electrolyte membrane fuel cell will be an important piece of technology for the overall transition from a petroleum-based economy to a renewable resource/hydrogen based one. At the heart of this essential device is a highly specialized polymer membrane that has been tailored to be highly proton conductive, while maintaining low permeability to the fuel gases and low electrical conductivity. Over extended operation times, it has been observed that various processes cause the membrane to degrade, resulting in ultimate failure of the fuel cell. Here, the morphologies present in a novel polymer electrolyte/poly(vinylidene fluoride) (PVDF) blend membrane are examined by transmission electron microscopy (TEM) for membranes and MEAs at the beginning and end of their life. Particular attention has been paid to changes in the polymer morphologies, as well as the spatial distribution of fluorine, sulfur, and other elements in the range of 5 to 100 nm. The effect of degradation and morphology change has been correlated to a decline in fuel cell performance over time.