Fabricating Nitrogen‐Rich Fe−N/C Electrocatalysts through CeO 2 ‐Assisted Pyrolysis for Enhanced Oxygen Reduction Reaction

Abstract The electrochemical oxygen reduction reaction (ORR) is a central process of various energy conversion systems. Yet, searching non‐noble‐metal electrocatalysts with superior ORR performance is still a great challenge. Herein, CeO 2 ‐loaded Fe−N/C catalysts (Fe−N/C−CeO 2 ) were prepared through a facile hydrothermal and pyrolysis method for enhanced ORR properties. The proper amount of CeO 2 can induce the anchoring of N species during the pyrolysis process, and increase the N‐containing active sites such as Fe−N x . Moreover, CeO 2 nanoparticles are capable of rapidly reducing the H 2 O 2 intermediate in ORR, further boosting the durability of the catalyst. Consequently, the Fe−N/C−CeO 2 (1 %) catalyst delivers prominent ORR performance with a half‐wave potential of 0.862 V and a diffusion limiting current density of 5.51 mA cm −2 in 0.1 M KOH, which is superior than that of the Fe−N/C catalyst, and even comparable to that of commercial Pt/C catalyst. Furthermore, the long‐term stability test of Fe−N/C−CeO 2 (1 %) shows a negative shift of just 18 mV of the half‐wave potential after 10000 cycles, which is much smaller than that of the Fe−N/C sample.