Iron‐Nitrogen Co‐doped Carbon with a Tunable Composition as Efficient Electrocatalysts for Oxygen Reduction.

Understanding the relationship between composition and activity is essential for the rational design of metal‐nitrogen‐Carbon (M−N−C) electrocatalysts for the oxygen reduction reaction (ORR). Here, a series of Fe‐N co‐doped porous carbon (Fe‐N−C) electrocatalysts are successfully prepared through the pyrolysis of ZIF‐8 doped with different amount of hemin. The catalyst (Fe55‐N−C) exhibits impressive ORR performance with an onset potential (Eonset) of 1.02 V (vs. RHE) and a half‐wave potential (E1/2) of 0.892 V in alkaline media, outperforming commercial Pt/C. Meanwhile, the average kinetic current density (Jk) of Fe55‐N−C at 0.850 V is 17.5 mA cm−2, which is 3.3‐fold higher than that of commercial Pt/C. Besides, it also delivers anti‐methanol poisoning ability and high durability. The high performance stems from the hierarchical porous structure, large specific surface area, and high dispersion of Fe‐Nx active sites in Fe55‐N−C. These findings could inspire new perspectives for rationally designing and synthesizing economical and practical non‐precious‐metal oxygen reduction electrocatalysts. [ABSTRACT FROM AUTHOR]