Cerium oxide nanoparticles (CNPs) are investigated as radical scavengers to increase the durability of polymer electrolyte membrane fuel cells (PEMFCs). However, the practical application of CNPs in PEMFCs is hindered by the low stability of the CNPs during cell operation and the low compatibility of the CNPs with PEM. In this study, as effective antioxidants for PEMs, surface-engineered CNPs, passivated with dopamine-based copolymer ligands containing multidentate catechol pendant groups (CNP@DPLs), are reported. The DPLs provide enhanced colloidal and chemical stability in acidic and radical environments, thanks to the robust catechol binding groups and polymer backbone shielding. It is highlighted that they also improved the redox cycling ability of the CNPs, with catechol's additional radical scavenging. Using the CNP@DPLs as a model system, the effect of surface charge is also examined. Negatively charged sulfonic acid-functionalized CNPs (CNP@DSAs) exhibit the highest compatibility with PEMs. Coherently, the CNP@DSA-based reinforced composite membrane (CNP@DSA-RCM) shows the lowest disintegration rate in Fenton's test. The PEMFC based on the CNP@DSA-RCM outperforms previously reported antioxidant-based PEMFCs. Importantly, while the pristine PEMFC and Ce salt-based one undergoes degradation after 40 h, the CNP@DSA based PEMFC retains its performance even after 100 h.
Bibliographical noteFunding Information:
H.K., S.H.Y., and H.Y.K. contributed equally to this work. This work was supported by the KIST Institutional Programs (2E31871), the program of Future Hydrogen Original Technology Development (NRF-2021M3I3A1082879), and Nano Future Material Technology Development (NRF-2020M3H4A3081817) through the National Research Foundation of Korea funded by Ministry of Science and ICT. This work was also supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by Ministry of Trade, Industry and Energy (MOTIE) (Nos. 20188550000440 and 20213030030260) and the Korea Medical Device Development Fund grant funded by the Korea government (the Ministry of Science and ICT, the Ministry of Trade, Industry and Energy, the Ministry of Health & Welfare, the Ministry of Food and Drug Safety [1711139068, KMDF_PR_20210525_0001]).
This study was funded by the AO Foundation.
© 2022 The Authors. Advanced Electronic Materials published by Wiley-VCH GmbH.
- cerium oxide
- proton exchange membrane fuel cells
- reinforced composite membranes
- surface passivation
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials