ABSTRACT Metal‐nitrogen‐carbon (M‐N‐C) catalysts are promising non‐precious metal catalysts for the oxygen reduction reaction (ORR), yet their practical application is hindered by insufficient long‐term stability. The limitation primarily stems from the generation of the two‐electron byproduct H 2 O 2 and the structural degradation of single‐atom sites. Herein, we report a radical‐scavenging strategy through the incorporation of non‐precious niobium nitride nanoparticles into a Fe‐N‐C matrix (FeNC‐NbN), which achieves exceptional ORR performance. The FeNC‐NbN catalyst exhibits a high half‐wave potential ( E 1/2 = 0.94 V RHE ) with negligible degradation. Furthermore, Zn‐air batteries equipped with FeNC‐NbN demonstrate outstanding performance, delivering a peak power density of 206.4 mW cm −2 and an ultralong cycling durability of 2400 h, surpassing most previously reported catalysts. Combined in situ Raman spectroscopy, in situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy analyses, and theoretical calculations reveal that the integration of NbN enhances ORR activity by increasing the pyrrolic N content within the FeNC framework. Concurrently, the vacant d ‐orbitals of Nb effectively interact with and scavenge free radicals, thereby protecting the active sites from degradation and ensuring excellent catalytic activity and stability. This work establishes a viable pathway for developing efficient and durable non‐precious ORR electrocatalysts.
Fan et al. (Tue,) studied this question.