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Transition metal nitrides (TMNs) are generally recognized as excellent electrocatalysts in aqueous solution because of their distinct electronic structures and high electrical conductivity. However, their potential catalytic activities are rarely studied in the oxygen electrodes of aprotic lithium–oxygen batteries and the intrinsic electroactivities are quite difficult to be manifested in binder‐involved electrodes. Herein, a novel combinational design of electronic structure and nanoarray architecture is proposed to eliminate the influences of binders and additives and achieve high performance of TMNs as oxygen electrodes for aprotic lithium–oxygen batteries. In the case study of CoN nanowire arrays (NAs), experimental coupled with theoretical studies demonstrate that the distinct electronic structure of CoN enables the appropriate adsorption and facile charge transfer between the discharge product Li2O2 and CoN. Results also show that the nanoarray architecture of CoN enables the full utilization of catalytic active sites, efficient mass transportation, and sufficient inner spaces for accommodating the insoluble discharge product. Thus, the CoN NA cathode achieves both a low overall overpotential of 1.01 V and a high areal capacity of 3.35 mA h cm−2. The combinational design principle of electronic structure and electrode architecture provides a promising way to develop advanced oxygen electrode for metal–air batteries.

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The robust porous architectures of active materials are highly desired for oxygen electrodes in lithiumoxygen batteries to enable high capacities and excellent reversibility. Herein, we report a novel three-dimensional replication strategy to fabricate three-dimensional architecture of porous carbon for oxygen electrodes in lithium-oxygen batteries. As a demonstration, ball-flower-like carbon microspheres assembled with tortuous hollow carbon nanosheets are successfully prepared by completely replicating the morphology of the nanostructured zinc oxide template and utilizing the polydopamine coating layer as the carbon source. When used as the active material for oxygen electrodes, the three-dimensional porous architecture of the prepared ballflower-like carbon microspheres can accommodate the discharge product lithium peroxide and simultaneously maintain the ions and gas diffusion paths. Moreover, their high degrees of defectiveness by nitrogen doping provide sufficient active sites for oxygen reduction/evolution reaction. Thus the prepared ball-flower-like carbon microspheres demonstrate a high capacity of 9,163.7 mA h g −1 and excellent reversibility. This work presents an effective way to prepare three-dimensional architectures of porous carbon by replicating the controllable nanostructures of transition metal oxide templates for energy storage and conversion applications.