Theoretical Insights into 4f–3d Synergistic Catalysis in Fe–Light Rare-Earth Atomic-Scale Catalysts for Oxygen Reduction

来源：ACS Publications

Sluggish oxygen reduction reaction (ORR) kinetics limit energy conversion efficiency, driving research interest in atomic-level catalysts. This work employs density functional theory calculations to investigate the ORR activity of Fe-based light rare-earth catalysts. Six Fe–light rare-earth configurations are constructed to reveal how 4f orbitals modulate the electronic structure of the Fe sites. Gibbs free energy analyses reveal synergistic catalysis between Fe and light rare-earth elements, enabling catalysts to optimize the reaction pathway and lower energy barriers of intermediates compared to single-atom catalysts. Among these, Fe–Nd–NC exhibits an ORR performance with an overpotential of only 0.55 V, an improvement over Fe–N–C and Nd–N–C. Electronic state analyses identify Fe atoms as active sites and Nd atoms as modulation centers. The 4f–3d coupling yields an optimal structure, optimizing the configuration of Fe sites and tuning the adsorption strength of intermediates. This study elucidates the origin of synergistic catalysis in Fe–light rare-earth catalysts, offering theoretical guidance for the design of ORR electrocatalysts.