Singlet Oxygen Induced Site‐Specific Etching Boosts Nitrogen‐Carbon Sites for High‐Efficiency Oxygen Reduction

Abstract

AbstractTargeted construction of carbon defects near the N dopants is an intriguing but challenging way to boost the electrocatalytic activity of N‐doped carbon toward oxygen reduction reaction (ORR). Here, we report a novel site‐specific etching strategy that features targeted anchoring of singlet oxygen (1O2) on the N‐adjacent atoms to directionally construct topological carbon defects neighboring the N dopants in N‐doped carbon (1O2−N/C). This 1O2−N/C exhibits the highest ORR half‐wave potential of 0.915 VRHE among all the reported metal‐free carbon catalysts. Pyridinic‐N bonded with a carbon pentagon of the neighboring topological carbon defects is identified as the primary active configuration, rendering enhanced adsorption of O2, optimized adsorption energy of the ORR intermediates, and a significantly decreased total energy barrier for ORR. This 1O2‐induced site‐specific etching strategy is also applicable to different precursors, showing a tremendous potential for targeted construction of high‐efficiency active sites in carbon‐based materials.