Document Type
Article
Abstract
Proton exchange membrane (PEM) fuel cells are promising for clean and efficient energy conversion across diverse applications. High-temperature PEM fuel cells (HT-PEMFCs) using phosphoric acid (PA)-doped polybenzimidazole (PBI) can operate up to 200°C, but at lower temperatures, water-induced PA loss often leads to performance degradation and reduced durability. In this work, we present a new class of main-chain ion-pair PBI membranes by integrating the imidazolium-biphosphate ion-pair units directly into the PBI backbone. This design results in membranes with high acid content, stronger acid-polymer interactions and stabilized acid retention. In single-cell tests, the Im+-PBI15-3 wt.% exhibits peak power densities of 0.79 W cm−2 at 160°C and 0.57 W cm−2 at 120°C, with excellent durability and minimal acid loss over prolonged operation. These results demonstrate that main-chain ion-pair PBIs offer a robust, high-performance solution for HT-PEMFC membranes capable of efficient operation down to 120°C.
Digital Object Identifier (DOI)
Publication Info
Published in Advanced Energy Materials, 2026, pages e70811-.
Rights
© 2026 The Author(s). Advanced Energy Materials published by Wiley-VCH GmbH This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
APA Citation
Lin, H., & Benicewicz, B. C. (2026). Main‐Chain Ion‐Pair Polybenzimidazole Membranes Enabling Reduced‐Temperature HT‐PEMFC Operation (Down to 120°C). Advanced Energy Materials.https://doi.org/10.1002/aenm.70811