Fe/Fe₃ C/N-Doped Carbon Materials from Metal-Organic Framework Composites as Highly Efficient Oxygen Reduction Reaction Electrocatalysts

A series of Fe/Fe₃ C-containing N-doped porous carbon materials (Fe/NC) were prepared by pyrolyzing composites that contained a metal-organic framework (MIL-88c-Fe) with dicyandiamide. The Fe/NC obtained at 800 °C (Fe/NC800) showed comparable onset potential and kinetics to that of the commercial Pt/C catalyst in catalyzing the oxygen reduction reaction (ORR). Further measurements suggested that it has better durability and much higher methanol tolerance than Pt/C. Acid leaching was performed to reveal the critical role of Fe-containing sites in ORR catalysis.