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

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–Nx 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–Nx 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–Nx and Fe–Nx 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.