Modulating Electronic Structures of Iron Clusters through Orbital Rehybridization by Adjacent Single Copper Sites for Efficient Oxygen Reduction

Abstract

AbstractThe atom‐cluster interaction has recently been exploited as an effective way to increase the performance of metal‐nitrogen‐carbon catalysts for oxygen reduction reaction (ORR). However, the rational design of such catalysts and understanding their structure‐property correlations remain a great challenge. Herein, we demonstrate that the introduction of adjacent metal (M)−N4 single atoms (SAs) could significantly improve the ORR performance of a well‐screened Fe atomic cluster (AC) catalyst by combining density functional theory (DFT) calculations and experimental analysis. The DFT studies suggest that the Cu−N4 SAs act as a modulator to assist the O2 adsorption and cleavage of O−O bond on the Fe AC active center, as well as optimize the release of OH* intermediates to accelerate the whole ORR kinetic. The depositing of Fe AC with Cu−N4 SAs on nitrogen doped mesoporous carbon nanosheet are then constructed through a universal interfacial monomicelles assembly strategy. Consistent with theoretical predictions, the resultant catalyst exhibits an outstanding ORR performance with a half‐wave potential of 0.92 eV in alkali and 0.80 eV in acid, as well as a high power density of 214.8 mW cm−2 in zinc air battery. This work provides a novel strategy for precisely tuning the atomically dispersed poly‐metallic centers for electrocatalysis.