Stable zirconium hydrogen phosphate-silica nanocomposite membranes with high degree of bound water for fuel cells

Zirconium hydrogen phosphate (ZrP)-silica nanocomposite polymer electrolyte membranes (PEMs) were prepared by sol-gel method in aqueous media. Hydrophilic and hydrophobic regions of PEMs were tailored by molecular level of architecture to introduce proton conducting pathways and methanol impervious nature. ZrP-silica nanocomposite PEMs showed improved thermal, mechanical, oxidative and hydrolytic stabilities along with high conductivity, methanol retention capacity, which are essential requirements. Furthermore, high degree of bound water content in membrane matrix indicates suitability of reported PEMs under anhydrous or low-humidity conditions. These PEMs were well processed as self-supporting film, and exhibited high selectivity parameter in comparison to Nafion117 membrane for direct methanol fuel cell (DMFC) applications.