Thermal properties of Nafion–TiO2 composite electrolytes for PEM fuel cell

Thermal analysis has been used to evaluate the stability, glass transition, and water retention of Nafion based polymer–ceramic electrolytes. These electrolytes are envisioned as promising replacement of Nafion in fuel cells operating above 100 °C. The polymeric matrix prepared by casting exhibits lower crystallinity than the extruded Nafion, a feature that affects the water absorption properties. The addition of titania-based nanotubes and nanoparticles to the polymer has enhanced the water retention at high temperatures (~130 °C) and the glass transition temperature, respectively. Such results are important for the design of composite electrolytes for the operation of fuel cells at high temperatures.