Investigation of Advanced Hybrid PEM Based on Sulfonyl Fluoride PFSA and Grafted Inorganic Nanoparticles

Nano-composite polymer electrolyte membranes were prepared by melt processing of sulfonyl fluoride form of perfluorosulfonic acid (PFSA) ionomer and two families of inorganic nanofillers, spherical nanoparticles of silicon dioxide prepared by sol-gel, and clay sepiolite ungrafted and grafted with alkyl-sulfonic acid moieties. This approach produces hybrid electrolyte membranes with substantially better properties when compared to reference (neat polymer) and commercial Nafion. The melt-extruded nano-composite electrolytes showed very efficient dispersion of the inorganic fillers, an overall improvement in thermal and dimensional stability, and improved conductivities between 10-2 to 10-3 S.cm-1 at 80{degree sign}C over the entire humidity range from 100 to 30%.