N-coordinated Fe–Co catalytic sites with interatomic cooperation for proton exchange membrane fuel cells

Abstract

Electrocatalysts featuring isolated Fe atoms integrated into carbon supports demonstrate exceptional oxygen reduction reaction (ORR) performance. Nonetheless, the efficiency and durability are often compromised by low active site density and the Fenton effect, particularly in acidic environments. In this work, we present a novel dual-metal catalyst that harnesses the synergistic interaction within a Co–Fe atomic configuration to boost catalytic efficiency while reinforcing stability, achieving a half-wave potential of 0.811 V in acidic electrolyte and exhibiting minimal activity degradation following 10 000 cycles in an accelerated durability assessment. Furthermore, this catalyst enables a proton exchange membrane fuel cell (PEMFC) to deliver a maximum power density of 455 mW cm⁻². Computational results show that the cooperative interaction between neighboring metals fine-tunes the d-band center of the metal sites, optimizing the adsorption of intermediates and, as a result, enhancing catalytic efficient. This study proposes an innovative approach to developing efficient dual-metal catalysts, advancing their potential for practical applications in PEMFCs.