Orderly Stacked “Tile” Architecture with Single-Atom Iron Boosts Oxygen Reduction in Liquid and Solid-State Zn–Air Batteries

Oxygen reduction reaction plays a crucial role in energy-related devices. However, four-electron transfer process involved in this reaction is usually constrained by sluggish kinetics. Single atomic (SA) Fe catalysts have attracted extensive attention due to the high atom utilization, yet the impact of the support architecture on accelerating the reaction has been largely overlooked. Inspired by the edge-rich and ordered tile that facilitates rainwater runoff, an orderly stacked “tile” carbon with highly dispersed SA Fe and doped S is prepared through the morphology-persistent conversion of a new metal–organic framework with a “tile” assembly. The catalyst exhibits a higher half-wave potential of 0.91 V in 0.1 M KOH, when compared with that of Pt/C and Fe atoms on a lamellar carbon. This is because the reaction kinetics is accelerated by the “tile” carbon architecture while the doped S weakens the Fe–O interaction, and decreases the *OH binding strength. Importantly, the catalyst, working at the air cathodes, powers the liquid and the solid-state Zn–air batteries to show high-power density and remarkable stability, and can effectively charge a mobile phone. This work not only provides an effective catalyst but also highlights the importance of “tile” architecture for developing advanced catalysts.