To cope with the demand for cleaner alternative energy, polymer electrolyte membrane fuel cells (PEMFCs) have received significant research attention owing to their high-power density, high fuel efficiency, and low polluting by-product. However, the water requirement of these cells has necessitated research on systems that do not require water and/or use other mediums with higher boiling points. In this work, a highly porous meta-polybenzimidazole (m-PBI) membrane was fabricated through the non-solvent induced phase inversion technique and thermal cross-linking for high-temperature PEMFC (HT-PEMFC) applications. Standard non-thermally treated porous membranes are susceptible to phosphoric acid (PA) even at low concentrations and are unsuitable as polymer electrolyte membranes (PEMs). With the porous structure of m-PBI membranes, higher PA uptake and minimal swelling, which is controlled via cross-linking, was achieved. In addition, the membranes exhibited partial asymmetrical morphology and are directly applicable to fuel cell systems without any further modifications. Membranes with insufficient cross-linking resulted in an unstable performance in HT-PEMFC environments. By optimizing thermal treatment, a high-performance membrane with limited swelling and improved proton conductivity was achieved. Finally, the m-PBI membrane exhibited enhanced acid retention, proton conductivity, and fuel cell performance.
Bibliographical noteFunding Information:
Funding: We acknowledge the financial support from Basic Science Research Program through the National Research Foundation (NRF) funded by the Ministry of Education [grant number NRF-2020R1A2C1009854]. It was also partially supported by Technology Development Program to Solve Climate Changes of The National Research Foundation (NRF) funded by the Ministry of Science, ICT & Future Planning [grant number NRF-2015M1A2A2056833].
© 2020 by the authors.
All Science Journal Classification (ASJC) codes
- Polymers and Plastics