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Branched Poly(Aryl Piperidinium) Membranes for Anion-Exchange Membrane Fuel Cells.

ABSTRACT: Anion-exchange membrane fuel cells (AEMFCs) are a promising, next-generation fuel cell technology. AEMFCs require highly conductive and robust anion-exchange membranes (AEMs), which are challenging to develop due to the tradeoff between conductivity and water uptake. Here we report a method to prepare high-molecular-weight branched poly(aryl piperidinium) AEMs. We show that branching reduces water uptake, leading to improved dimensional stability. The optimized membrane, b-PTP-2.5, exhibits simultaneously high OH^- conductivity (>145 mS cm^-1 at 80 °C), high mechanical strength and dimensional stability, good processability, and excellent alkaline stability (>1500 h) in 1 M KOH at 80 °C. AEMFCs based on b-PTP-2.5 reached peak power densities of 2.3 W cm^-2 in H₂ -O₂ and 1.3 W cm^-2 in H₂ -air at 80 °C. The AEMFCs can run stably under a constant current of 0.2 A cm^-2 over 500 h, during which the b-PTP-2.5 membrane remains stable.

SUBMITTER: Wu X

PROVIDER: S-EPMC9304273 | biostudies-literature |

REPOSITORIES: biostudies-literature

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