Journal
APPLIED CATALYSIS B-ENVIRONMENTAL
Volume 309, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.apcatb.2022.121290
Keywords
Oxygen reduction reaction; Fe-N-C; Stability; Demetallation; Mossbauer spectroscopy
Funding
- National Natural Science Foundation of China [22109161, 22005300]
- Postdoctoral Science Foundation of China [2021M693130]
Ask authors/readers for more resources
This study reveals the significant influence of the structure and structural evolution of FeN4 site in Fe-N-C catalysts on the activity and stability of oxygen reduction reaction. The key challenge lies in solving the demetallation issue.
Iron-nitrogen-carbon (Fe-N-C) catalysts for oxygen reduction reaction (ORR) are promising candidates in fuel cell devices but the poor stability remains a grave challenge. The elimination of demetallation is pivotal for extending the life but still incapable due to the ambiguous mechanism. Herein, we show that the structure of FeN4 site and its structural evolution during ORR has the significant influence. The end-of-test/in-situ Mossbauer spectroscopy and density functional theory study reveal that D1 mainly contributes to the ORR activity but suffers severe demetallation, which is likely due to the instability of FeN4C8. The faster demetallation during ORR, especially at higher potential, can be attributed to the weaker coordination of FeN4 induced by oxygenated intermediate and electric field according to ab initio molecular dynamics simulations. Finally, the binding energy of Fe-N bond is introduced to describe the influence of structure and structural evolution and give guidance to the improvement of stability.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available