Functionalized POSS-Modified SEBS-Based Composite Anion-Exchange Membranes for AEMFCs

Inspired by the strategy of rubber reinforcement, the N-methylpiperidium functionalized POSS was designed and synthesized to improve the ion conductivity as well as the mechanical and thermal properties of SEBS-based anion-exchange membranes (AEMs). A series of Pi-POSSx%/Pi-SEBS AEMs were prepared and assembled into MEAs for the fuel cell performance test. The addition of Pi-POSS fillers significantly enhanced the comprehensive performance of the AEMs. Especially, the Pi-POSS15%/Pi-SEBS composite membrane with the highest IEC value exhibited ion conductivities of 30.70 mS cm–1 at 30 °C and 69.11 mS cm–1 at 80 °C and the best alkaline stability. The Pi-POSS15%/Pi-SEBS composite membrane showed a maximum power density of 219 mW cm–2 at 80 °C, which was higher than the original Pi-SEBS membrane (117 mW cm–2). This work discloses a promising approach for improving the AEM performance with well-designed inorganic–organic composite fillers