Single atomic cobalt electrocatalyst for efficient oxygen reduction reaction

Abstract

Robust oxygen reduction reaction (ORR) catalysts are essential for energy storage and conversion devices, but their development remains challenging. Herein, we design a single-atom catalyst featuring isolated Co anchored on nitrogen-doped carbon (Co-SAC/NC) via a highly efficient “plasma-bombing” strategy. With a high loading (up to 2.5 ​wt%), the well-dispersed single Co atoms in Co-SAC/NC give it robust ORR performance in an alkaline medium. It also demonstrates excellent battery performance when implemented as the air-cathode catalyst in a zinc-air battery (ZAB). Theoretical calculations reveal that the Co–N4 moiety experiences an “extraction/recovery” structural evolution during the ORR process, and the reaction's rate-determining step is the formation of OOH∗ (reaction intermediate). This work provides a new strategy for designing robust ORR catalysts for high-performance ZABs and other energy-conversion devices.