Preparation and characterization of zirconium phytate as a novel solid intermediate temperature proton conductor

Zirconium phytate (ZrPA) was prepared via gelation of zirconyl chloride and phytic acid in certain ratios. Fourier-transform infrared spectroscopy was applied to confirm the structure and interactions between Zr4+ and phytate ions, including hydrogen bonding and chelation. Scanning and transmission electron microscopic study have shown that ZrPA has a fusiform shape and a layered structure. Good thermal stability up to 250 °C was obtained. ZrPA(3:4) exhibited an ion exchange capacity of 1.04 meq g−1. At 140 °C, the proton conductivity of ZrPA(3:4) was 0.099 S cm−1 at 100% RH, 0.042 S cm−1 at 50% RH and 0.018 S cm−1 at 0RH.