Electrocatalysts for Zinc–Air Batteries Featuring Single Molybdenum Atoms in a Nitrogen‐Doped Carbon Framework

Abstract

Bifunctional catalysts can facilitate two different electrochemical reactions with conflicting characteristics. Here, a highly reversible bifunctional electrocatalyst for rechargeable zinc–air batteries (ZABs) is reported featuring a “core–shell structure” in which N‐doped graphene sheets wrap around vanadium molybdenum oxynitride nanoparticles. Single Mo atoms are released from the particle core during synthesis and anchored to electronegative N‐dopant species in the graphitic shell. The resultant Mo single‐atom catalysts excel as active oxygen evolution reaction (OER) sites in pyrrolic‐N and as active oxygen reduction reaction (ORR) sites in pyridinic‐N environments. ZABs with such bifunctional and multicomponent single‐atom catalysts deliver high power density (≈376.4 mW cm⁻²) and long cycle life of over 630 h, outperforming noble‐metal‐based benchmarks. Flexible ZABs that can tolerate a wide range of temperatures (−20 to 80 °C) under severe mechanical deformation are also demonstrated