Abstract: | A bifunctional oxygen electrocatalyst composed of iron carbide (Fe3C) nanoparticles encapsulated by nitrogen doped carbon sheets is reported. X‐ray photoelectron spectroscopy and X‐ray absorption near edge structure revealed the presence of several kinds of active sites (Fe?Nx sites, N doping sites) and the modulated electron structure of nitrogen doped carbon sheets. Fe3C@N‐CSs shows excellent oxygen evolution and oxygen reduction catalytic activity owing to the modulated electron structure by encapsulated Fe3C core via biphasic interfaces electron interaction, which can lower the free energy of intermediate, strengthen the bonding strength and enhance conductivity. Meanwhile, the contribution of the Fe?Nx sites, N doping sites and the effect of Fe3C core for the electrocatalytic oxygen reaction is originally revealed. The Fe3C@N‐CSs air electrode‐based zinc‐air battery demonstrates a high open circuit potential of 1.47 V, superior charge‐discharge performance and long lifetime, which outperforms the noble metal‐based zinc‐air battery. |