Novel perovskite structured calcium titanate-PBI composite membranes for high-temperature PEM fuel cells: Synthesis and characterizations

We report the incorporation of nanoCTO (nanoCaTiO3), prepared by sol-gel methods into the synthetic m-PBI to develop nanoCTO-PBI composite membranes. The macromolecular structure of the membrane shows high conductivity and good oxidative stability. The acid doping level in the membrane was estimated by the amount of phosphoric acid (PA) per specific volume. Increase in the content of nanoCTO results in the increase in conductivity as well as the oxidative stability of the membrane. Higher conductivity observed for 15% nanoCTO-PBI composite membrane as 32.7 mS cm−1, whereas that of 5% nanoCTO-PBI is only 20.2 mS cm−1. The power density and current density of 10% nanoCTO-PBI composite membrane at 0.6 V and 160 °C obtained are 251.4 mW cm−2 and 419 mA cm−2 respectively. Thus, the composite membranes are found to be potential electrolytes for HT-PEM fuel cells with enhanced proton conductivity.