Cu/Fe embedded N-doped carbon as a highly durable oxygen reduction electrocatalyst

Abstract

Dual metal atoms embedded into carbon are emerging electrocatalysts due to synergistic interaction. Herein, copper and iron dual-atoms embedded in a nitrogen-doped carbon support with abundant metal–nitrogen moieties are fabricated via zinc imidazole framework pyrolysis. Hollow nitrogen-doped carbon (HNC) containing Cu/Fe–N_x moieties (Cu : Fe/HNC) shows excellent oxygen reduction activity with a half-wave potential of 0.84 V in alkaline media. Furthermore, the Cu : Fe/HNC exhibits remarkable stability and strong anti-poisoning ability due to the synergistic interaction of the Cu/Fe–N_x moieties in the HNC architecture. Density functional theory calculations revealed the optimum adsorption and desorption of oxygen intermediates due to the synergistic interaction of Cu–N_x and Fe–N_x sites, resulting in improved oxygen reduction performance. This work provides a facile synthesis of dual metal atom catalysts for developing low-cost, nonprecious metal-based ORR electrocatalysts.