Atomic ternary-doped MnCoZn-N-C for efficient oxygen electroreduction

Abstract

The oxygen reduction reaction (ORR) is crucial for harnessing the clean energy stored in hydrogen and inexpensive metals, but its practicality has been severely hampered by the lack of high-performance, inexpensive electrocatalysts. Here, a new type of ORR electrocatalyst is developed that reflects the atomic dispersion of ternary Mn, Co, and Zn species in highly N-doped carbon substrate, strong synergies in ternary metallic components have been experimentally demonstrated for the exceptional ORR performance, which is most likely contributed by the densely distributed ternary metal/nitrogen moieties. As a result, the ternary MnCoZn-NC obtained an initial potential of 0.99 V and a half-wave potential of 0.88 V for promoting ORR in alkaline and an open circuit voltage of 1.49 V, a power of 120 mW cm−2 when used as a cathode for the Zn-air battery assembly. Our work successfully attempts the implantation of ternary Mn, Co, and Zn species into porous carbon, which might suggest the controllable synthesis of other types of multi-metal-doped carbon electrocatalysts.