Pyrene containing, highly conductive and robust poly (aryl piperidinium) anion exchange membranes for fuel cell applications

Abstract

Anion exchange membrane fuel cells (AEMFCs) stand out as an advanced energy technology, featuring non-precious metals usable as catalysts to yield superior oxygen reduction kinetics compared with proton exchange membrane fuel cells. The quest for high-performance and durable anion exchange membranes (AEMs) is a primary focus in the development of AEMFCs. In this study, we have fabricated innovative series of AEMs by synthesizing a copolymer from disk shaped pyrene, 1-methyl-4-piperidone, and p-terphenyl, followed by the quaternization process of the produced polymer. AEMs incorporating pristine pyrene can enhance the microphase separation and free volume. This structural modification produces both free volume and localized stacking effect, which facilitates the creation of ion channels with reduced OH^- transport resistance. Notably, the synthesized qPPTP-10 AEM demonstrates significantly enhanced ion conductivity of 166.5 mS cm⁻¹ at 80 °C and 181.13 mS cm⁻¹ at 90 °C. Furthermore, the membrane exhibits impressive alkaline stability, with ion conductivity retention of 96.5 % and 86.2 % after 1500 h of treatment in 1 M and 2M NaOH, respectively at 80 °C. Moreover, qPPTP-10 based H₂-O₂ single cell achieves a peak power density of 1374 mW cm^-2 at 80 °C and durability greater than 60 h.