Uniformly dispersed Fe3C (~5 nm) in Fe-N-doped carbon nanosheets derived from coal tar pitch as efficient electrocatalysts for oxygen reduction reaction

Abstract

It is of great significance to rationally design and synthesis low-cost catalysts for oxygen reduction reaction (ORR) with excellent catalytic activity for the application of fuel cell devices. Herein, a facile and cost-effective strategy is developed to prepare iron-nitrogen-doped carbon nanosheets with uniformly dispersed Fe3C nanocrystals (~5nm) encapsulated in graphitic layers (Fe3C@Fe-N-CNSs) by pyrolyzing a mixture of ferrocene-containing coal tar pitch and melamine. The optimized Fe3C@Fe-N-CNSs catalyst shows significantly improved ORR catalytic activity (onset potential 1.04 V) and a much better methanol tolerance than that of commercial Pt/C (onset potential 1.02 V) in an alkaline medium. This work paves a path for the preparation of low-cost and high-performance ORR electrocatalysts for fuel cells.