Atomic Fe-N4 sites on electrospun hierarchical porous carbon nanofibers as an efficient electrocatalyst for oxygen reduction reaction

Porous carbon materials doped with atomically dispersed metal sites (ADMSs) are promising electrocatalysts for oxygen reduction reaction (ORR) electrocatalysis. In this work, we fabricated hierarchical porous nitrogen-doped carbon nanofibers with atomically dispersed Fe-N4 sites by carbonization of electrospinning iron-based metal-organic frameworks (MOFs)/polyacrylonitrile nanofibers for ORR electrocatalysis. Remarkably, the resultant carbon nanofibers with atomically dispersed Fe-N4 sites exhibit extraordinary electrochemical performance with an onset potential of 0.994 V and a halfwave potential of 0.876 V in alkaline electrolyte, comparable to the benchmark commercial Pt/C catalyst. The high catalytic performance is originated from the unique hierarchically porous 1D carbon structure and abundant highly active atomically dispersed Fe-N4 sites.