Janus transition metal dichalcogenide monolayers (TMDs) have attracted wide attention due to their unique physical and chemical properties since the successful synthesis of the MoSSe monolayer. However, the related studies...

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Lithium–air batteries (LABs) have attracted intense interest due to their ultrahigh energy density. However, the performance of LABs has to depend on modified electrolytes, gas selective film and Li anode protection. In this study, firstly it is reported that Mo‐O octahedron induced subcrystalline scheelite CoMoO4 catalyst achieves a high performance LABs performance based only on the high catalytic activity in air. The subcrystalline CoMoO4 catalyst obtains a specific capacity of 12 000 mAh g−1, and ultralong cycle stability over 270 cycles at 1000 mA g−1 in ambient air. This study demonstrates an ultrastable crystal structure and surface conditions of the CoMoO4 catalyst toward a corrosive environment and complex air‐involved reactions. A theoretical calculation further reveals that the polyhedral framework in the scheelite CoMoO4 can provide a highly stable catalytic surface for the OER/ORR reactions, furthermore, its repulsive nature toward H2O and CO2 can efficiently avoid side reactions and slow the corrosion of the Li anode in air. Moreover, the induced octahedron enhances the adsorption energies to O2 and LiO2, and accelerates the catalytic reactions in air. The present study provides a conceptual breakthrough to find highly active cathode catalysts for LABs.

Lithium–air batteries (LABs), owing to their ultrahigh theoretical energy density, are recognized as one of the next‐generation energy storage techniques. However, it remains a tricky problem to find highly active cathode catalyst operating within ambient air. In this contribution, a highly active Fe2Mo3O12 (FeMoO) garnet cathode catalyst for LABs is reported. The experimental and theoretical analysis demonstrate that the highly stable polyhedral framework, composed of FeO octahedrons and MO tetrahedrons, provides a highly effective air catalytic activity and long‐term stability, and meanwhile keeps good structural stability. The FeMoO electrode delivers a cycle life of over 1800 h by applying a simple half‐sealed condition in ambient air. It is found that surface‐rich Fe vacancy can act as an O2 pump to accelerate the catalytic reaction. Furthermore, the FeMoO catalyst exhibits a superior catalytic capability for the decomposition of Li2CO3. H2O in the air can be regarded as the main contribution to the anode corrosion and the deterioration of LAB cells could be attributed to the formation of LiOH·H2O at the end of cycling. The present work provides in‐depth insights to understand the catalytic mechanism in air and constitutes a conceptual breakthrough in catalyst design for efficient cell structure in practical LABs.