Electron‐Donors–Acceptors Interaction Enhancing Electrocatalytic Activity of Metal‐Organic Polymers for Oxygen Reduction

Abstract Catalysts with metal‐N x sites have long been considered as effective electrocatalysts for oxygen reduction reaction (ORR), yet the accurate structure‐property correlations of these active sites remain debatable. Report here is a proof‐of‐concept method to construct 1,4,8,11‐tetraaza14annulene (TAA)‐based polymer nanocomposites with well‐managed electronic microenvironment via electron‐donors/acceptors interaction of altering electron‐withdrawing β‐site substituents. DFT calculation proves the optimal −Cl substituted catalyst (CoTAA−Cl@GR) tailored the key OH* intermediate interaction with Co−N 4 sites under the d ‐orbital regulation, hence reaching the top of ORR performance with excellent turnover frequency (0.49 e s −1 site −1 ). The combination of in situ scanning electrochemical microscopy and variable‐frequency square wave voltammetry techniques contribute the great ORR kinetics of CoTAA−Cl@GR to the relatively high accessible site density (7.71×10 19 site g −1 ) and fast electron outbound propagation mechanism. This work provides theoretical guidance for rational design of high‐performance catalysts for ORR and beyond.