Decorating Single‐Atomic Mn Sites with FeMn Clusters to Boost Oxygen Reduction Reaction

Abstract The regulation of electron distribution of single‐atomic metal sites by atomic clusters is an effective strategy to boost their intrinsic activity of oxygen reduction reaction (ORR). Herein we report the construction of single‐atomic Mn sites decorated with atomic clusters by an innovative combination of post‐adsorption and secondary pyrolysis. The X‐ray absorption spectroscopy confirms the formation of Mn sites via Mn‐N 4 coordination bonding to FeMn atomic clusters (FeMn ac /Mn‐N 4 C), which has been demonstrated theoretically to be conducive to the adsorption of molecular O 2 and the break of O−O bond during the ORR process. Benefiting from the structural features above, the FeMn ac /Mn‐N 4 C catalyst exhibits excellent ORR activity with half‐wave potential of 0.79 V in 0.5 M H 2 SO 4 and 0.90 V in 0.1 M KOH as well as preeminent Zn‐air battery performance. Such synthetic strategy may open up a route to construct highly active catalysts with tunable atomic structures for diverse applications.