Conductive and Stable Crosslinked Anion Exchange Membranes Based on Poly(arylene ether sulfone)

Abstract

Highly conductive and stable anion exchange membranes (AEMs) are important components of high-performance anion exchange membrane fuel cells (AEMFCs). Here, we report the use of crosslinked poly(arylene ether sulfone) (PAES) AEMs containing quaternary ammonium (QA) and triazolium cations. The crosslinked PAES-triazole-hydroxide membrane (cPAES-TA-OH) had a higher ion exchange capacity (IEC) than that of the non-crosslinked membrane (PAES-TA-OH) owing to the presence of triazolium cations. The IEC values of cPAES-TA-OH and PAES-TA-OH were 1.75 and 1.31 meq/g, respectively. The IEC value affects the water uptake and swelling ratio of a membrane. The water uptake and swelling ratio of cPAES-TA-OH were higher than those of PAES-TA-OH at 30 °C and 80 °C. In addition, hydroxide conductivity and membrane stability were enhanced by crosslinking; the hydroxide conductivity of cPAES-TA-OH was 92.1 mS/cm at 80 °C under 95% RH (in contrast to 86.2 mS/cm for PAES-TA-OH), and its conductivity retention was 67% after treating with 1M NaOH at 80 °C for 24 h (in contrast to 51% for PAES-TA-OH).