Hollow onion-like graphitic nanoshell structured Fe-N/C nanofiber (Fe-N/CNF) catalyst with porous morphology was prepared by heat treating as-spun polyacrylonitrile/ferrous oxalate composite nanofibers in ammonia atmosphere for the first time. These porous electrocatalyst showed both excellent catalytic activity for oxygen reduction reaction (ORR) and much better stability than commercial Pt/C catalyst in acid solution. The Fe-N/CNF catalysts developed here could be easily fabricated on a large scale and show high potential in proton exchange membrane fuel cells (PEMFCs). (C) 2013 Elsevier B.V. All rights reserved