Anchoring Iron‐EDTA Complex on Graphene toward the Synthesis of Highly Efficient Fe‐N‐C Oxygen Reduction Electrocatalyst for Fuel Cells

Developing nonprecious carbon electrocatalysts as alternatives to platinum for cathodic oxygen reduction reaction in fuel cells is of significance. Herein, an efficient precursor‐controlled synthesis strategy based on extremely rapid nucleation and deposition process assisted by the liquid nitrogen freeze drying method is explored to anchor cheap iron‐EDTA complex evenly dispersed on graphene to realize microstructural homogeneity of the derived Fe‐N‐C oxygen reduction electrocatalyst. The prepared electrocatalyst possesses excellent performance including high activity with more positive onset and half‐wave potential, such long‐term stability, and anti‐poisoning effect compared to commercial Pt/C. The activity correlates well with the unique sheet‐shaped morphology, high surface area, hierarchical porous structure, and the introduction of Fe‐Nx/C species. Especially, both the assembled practical alkaline and acid fuel cells based on the synthesized cathode catalysts reveal excellent performance with high open‐circuit voltage and power density.