Alloyed Co-Mo Nitride as High-Performance Electrocatalyst for Oxygen Reduction in Acidic Medium

Exploring cheap and stable electrocatalysts to replace Pt for the oxygen reduction reaction (ORR) is now the key issue for the large-scale application of fuel cells. Herein, we report an alloyed Co-Mo nitride electrocatalyst supported on nitrogen-doped carbon nanocages (NCNCs) which combines the merits of cobalt nitride and molybdenum nitride, showing high activity comparable to that of cobalt nitride and progressively enhanced stability with the increase in the Mo ratio. The typical Co0.5Mo0.5Ny/NCNCs catalyst demonstrates excellent ORR performance in acidic medium with a high onset potential of 808 mV vs RHE, superior stability (>80% retention after 100 h of continuous testing in 0.5 mol H2SO4), a dominant four-electron catalytic process, and good immunity to methanol crossover. Together with the convenient, and scalable preparation as well as the low cost, the alloyed Co-Mo nitride electrocatalyst shows great potential in application for fuel cells. This study also suggests a promising strategy to develop non-precious-metal ORR. electrocatalysts in acidic medium: i.e., to construct the alloyed compounds by combining substances with respective high activity and high stability.