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

摘要

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,a 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.