Enhancing PEM fuel cell performance and durability with CeO₂-Modified Fe-N-C hollow-fiber cathodes

In this study, Fe-N-C catalyst-based hollow-fiber cathodes were fabricated via a core-shell electrospinning technique to increase surface area, promote uniform catalyst and Nafion (R) distribution, and achieve highly conductive and porous cathode structures for proton exchange membrane (PEM) fuel cells. Morphological analysis confirmed the successful fabrication of Fe-N-C hollow-fiber cathodes with a highly porous structure, as verified by porosimetry. Membrane electrode assemblies (MEAs) incorporating these cathodes (3.0 mg.cm(-2) Fe-N-C) were evaluated for fuel cell performance and durability and compared to MEAs using air-sprayed and single-fiber cathodes. The effect of cerium oxide (CeO2) as a radical scavenger was also investigated to improve durability of the electrode. Among the tested configurations, hollow-fiber cathodes with CeO2 exhibited superior performance, achieving a peak power density of 96.1 mW.cm-2 at end-of-test (EOT) with a 14.4 % improvement compared to CeO2-free cathode. Single-fiber cathodes with CeO2 also showed enhanced performance, attributed to reduced hydrogen peroxide (H2O2) formation. Electrochemical impedance spectroscopy (EIS) confirmed the role of CeO2 in suppressing H2O2 formation, thereby improving both performance and durability. These results highlight the potential of CeO2-modified Fe-N-C hollow-fiber cathodes as promising cathode materials for PEM fuel cells.