MnO Enabling Highly Efficient and Stable Co‐N_x/C for Oxygen Reduction Reaction in both Acidic and Alkaline Media

Abstract In situ growing transition metals on N‐doped carbon by atomic doping produces a class of promising alternatives to replace Pt‐based catalysts for redox reactions, yet still suffer from unsatisfactory activity and durability in acidic and basic media. Herein, a simple synthetic strategy to fabricate an MnO modifying Co‐N_x/C catalyst with high activity and robust durability is presented. The interphase engineering well controls the Co and N species in the carbon matrix, affording the material with more pyridine N and graphite N; the interaction between Co‐N_x and MnO phase is also well discussed. Accordingly, the obtained Co‐N_x/C‐MnO catalyst exhibits excellent electrocatalytic properties towards oxygen reduction reaction, achieving a half‐wave potential of 0.87 and 0.66 V versus reversible hydrogen electrode in 0.1 m KOH and 0.1 m HClO₄ solutions, as well as excellent durability with only −16.9 and −12.2 mV shift after 1000 cycles, respectively. This study provides insights into the design of noble‐metal‐free electrocatalysts from the perspective of active sites and catalyst carriers.