Preparation and Characterization of Phosphated Titania/Nafion® Composite Membranes

Phosphated titania (PO43--TiO2) was synthesized and reinforced into Nafion (R) membrane to prepare a polymer electrolyte membrane (PEM). Phosphated titania on a nanometric level were synthesized and characterized by X-ray diffraction, Fourier transform infrared spectroscopy and energy dispersive spectroscopy (EDS). 2.61 wt% of phosphorus was successfully incorporated into the titanium surface and confirmed by EDS. A small amount of phosphated titania ranging from 0.5-3 wt% based on the Nafion (R) wt% was then reinforced into the Nafion (R) membrane by water assisted solution casting. The added phosphated titania were well dispersed in the phosphated titania/Nafion (R) composites which were characterized by thermogravimetric analysis, ion exchange capacity (IEC), and methanol uptake. The results showed that the phosphated titania/Nafion (R) composites produced enhanced thermal stability compared to the neat Nafion (R) membrane and had lower methanol uptake while maintaining IEC values.