INFLUENCE OF PRE-TREATMENT ON PHYSICO-CHEMICAL AND ELECTROCHEMICAL PROPERTIES OF PIPERION MEMBRANES FOR AEMFC APPLICATIONS

The fuel cell industry stands out as one of the most promising sectors for advancing technologies aimed at sustainable energy generation. In particular, Anion Exchange Membrane Fuel Cells (AEMFCs) have garnered significant attention due to their ability to utilize low-platinum or nonplatinum catalysts and their relatively low activation energy for the oxygen reduction reaction. The overall performance of AEMFCs is closely linked to the intrinsic properties of the Anionic Exchange Membrane (AEM). The AEMs are crucial for achieving high power density and their stability and durability being determinants for long-term operation cells. Recent advances in AEMFCs research have likely contributed to the development of innovative commercial membranes, such as PiperION®. This poly(aryl piperidinium)-based AEM demonstrates superior wet/dry cycling stability, marking a significant step forward in membrane technology1. In an AEMFC, OH- are the dominant anions transported through the exchange membrane from the cathode to the anode side of the cell. PiperION has a very high potential for ionic conductivity due mobility within the membrane. Different pre-treatments, in terms of KOH concentration and time exchange, were evaluated to understand the effect on the final properties of the membrane. It was found that a fast ion exchange kinetic occurred after one hour in KOH 0.5M, indicating the complete ion conversion. The nominal IEC value (2.42 meq/g) was reached using a mild ionexchange conditions. No degradation of the functional groups was highlighted, and a contained swelling was measured at 60°C. Anion conductivity was carried out increasing the temperature over 60°C, considered a critical temperature for anion-exchange membranes, reaching values higher than 100 mS/cm.