Single-atom Fe-N-G as an efficient electrocatalyst for oxygen reduction reaction

It is essential for rapid development of fuel cell to study the non-noble metal oxygen reduction catalyst with high efficiency to replace the precious metal Pt. In this paper, the complex of iron and 1,10-Phenanthroline hydrochloride (Fe-Phen) has been loaded on graphene oxide sheets, and the single-atom Fe-N-G catalyst is synthesized after being thermally treated. It can be seen that the single metal iron atom is conformed to be dispersed on the surface of the defective multilayer graphene through aberration-corrected high angle annular dark-field scanning transmission electron microscope (AC-HAADF-STEM). The prepared catalyst exhibited excellent oxygen reduction performance in 0.1 mol L-1 KOH solution with half wave potential of 0.881 V, which is higher than that of 20 wt% Pt/C (0.851 V). In addition, Fe-N-G also shows higher methanol tolerance and outstanding stability. In contrast, Pt/C is slightly inferior in the above performances. It is expected that the single atomic iron catalysts with excellent performance may replace Pt/C in membrane fuel cells.