Cationic groups in polystyrene/O-PBI blends influence performance and hydrogen crossover in AEMWE

This study examines the effect of various quaternary ammonium groups on AEMWE performance and hydrogen crossover in blends of quaternized polystyrenes with O-PBI. Due to their higher hydroxide conductivity (69 mS cm^-1 at 80 °C, 90% RH), trimethylammonium groups enable AEMWE to reach 1.0 A cm^-2 at 2.0 V. The trimethylammonium groups exhibit low hydrogen crossover, ranging from 1.5% to 0.3%, across current densities of 50 to 1000 mA cm^-2. Low hydrogen crossover is essential for AEMWE in terms of safety and efficiency.