A new sulfonated poly(ether sulfone) hybrid with low humidity dependence for high-temperature proton exchange membrane fuel cell applications

A new sulfonated poly(ether sulfone) (PES) hybrid with low humidity dependence was prepared based on a new synthesized PES and Udel as a commercial PES. The PES was synthesized based on a pyridine containing diol which is able to change between pyridine and pyridinium salt forms during the cell performance (acidic condition) and facilitate proton transfer. The presence of nitrogen group increases inter and intramolecular interactions in the membrane and enhance proton hopping mechanism. Thermogravimetrical analysis of PES hybrid shows good thermal stability. Proton conductivity measurements were evaluated on a fuel cell test station, showing that the membrane has better performance under lower humidity (relative humidity=60%) compare to the fully hydrated condition (relative humidity=100%). The results reveal that proton transfer might be mainly accomplished through proton hopping mechanism at higher temperatures. The membrane also shows significant proton conductivity at 120 degrees C (about 6.6 mScm(-1) at RH=30%). (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45342.