Harnessing atomically precise Fe-Nx motifs within hierarchical porous carbon-MOF matrices for next-generation ultrastable high-energy lithium–oxygen batteries

Lithium-oxygen batteries (LOBs), with ultrahigh energy density (>3500 Wh kg −1 ), are limited by synergistic degradation (Lithium peroxide (Li 2 O 2 ) passivation, kinetic polarization, mass transport issues) in conventional electrodes. This work proposes a multi-hierarchy electrode architecture combining three-dimensional ordered hierarchically porous carbon matrices (3DOH) and Fe single atoms. The 3DOH carbon, synthesized via templated ZnFe-ZIF pyrolysis, features interconnected macropores (≥200 nm) for rapid ion/oxygen transport and mesopores (2–50 nm) with atomically dispersed Fe-N x sites for bifunctional catalysis. Metal-organic framework (MOF) scaffolds enhance mechanical stability while maintaining conductivity. The design achieves 17334 mAh g −1 capacity at 200 mA g −1 (69.5% enhancement over conventional electrodes) and 132-cycle stability with minimal overpotential degradation (ΔV < 0.93 V). By synergizing macroscopic kinetics and Ångstrom-level reactivity, this architecture offers a scalable paradigm for high-energy, long-life LOBs systems. Future directions include atomic-level mechanistic studies and industrial-scale synthesis.