Pyrolysis‐Mediated Polycyano Strategy for Directed Construction of Fe 3 C‐Synergized Fe─N Carbon Nanotubes Heterostructure Toward High‐Efficiency Oxygen Reduction Reaction

Abstract Precise modulation of the coordination environment of Fe─N x sites is crucial yet challenging for enhancing the intrinsic activity of single‐atom Fe/N‐codoped carbon catalysts toward the oxygen reduction reaction (ORR). Herein, N‐doped carbon nanotubes embedded with Fe 3 C nanoparticles with abundant pyridinic‐N and Fe─N x active sites are prepared by simple pyrolysis of precursors containing Zn 2+ /Fe 2+ and cyano groups. The optimized Fe 3 C/FeN@CNT‐900 catalyst exhibits a remarkable ORR half‐wave potential ( E 1/2 ) of 0.89 V versus RHE, along with exceptional methanol tolerance and SCN − resistance. The power density of the zinc‐air battery with this cathode achieves 1.65 times of that of the battery using the Pt/C+RuO 2 catalyst. Experimental and theoretical analyses reveal that these enhancements arise from tailored electronic structures and optimized intermediate adsorption at Fe active centers. Synergistic catalysis between atomic Fe─N x sites and Fe 3 C nanoparticles lowers the energy barrier of the ORR rate‐determining step by facilitating interfacial electron transfer, as evidenced by density functional theory calculations. This work provides a rational strategy for designing high‐performance dual‐active sites in metal‐nitrogen‐carbon electrocatalysts and highlights the critical role of atomic‐nanoparticle interactions in advanced energy conversion systems.