Modulating p-Band Center of M-N₄ Site via Engineering Second-Shell Carbon Defects for High-Performance Lithium-Carbon Composite Anodes

Lithium (Li) metal anodes remain commercially constrained by irreversible losses from inherent electrochemical activity. While carbon-based materials mitigate Li metal deterioration through regulated deposition, dendrite suppression, and volume accommodation, the fabrication of stable Li─C composite anodes is consistently hindered by the intrinsic lattice mismatch. To address this atomic-scale incompatibility, we engineer carbon defects adjacent to single-atom Zn-N₄ sites with high dispersibility (denoted as ZND), altering their symmetrical electron distribution to release stronger electroactivity, using metal-polyphenol coordination and structural rearrangement. Theoretical simulations indicate that the electronic configuration is reconstructed, and the p-band center of the electronegative nitrogen atoms located in the first shell is significantly elevated, notably intensifying the interaction with the molecular orbitals of the reactant Li⁺. Experimental characterization confirms that ZND optimizes Li hetero-nucleation behavior, promoting the formation of dense Li deposition layers and an inorganic-rich solid electrolyte interface (SEI). The Li||ZND half-cell achieves over 450 cycles of stable cycling at current densities of 1.0 and 2.0 mA cm⁻², respectively, with a fixed areal capacity of 1.0 mAh cm⁻². Consequently, the fabricated Li─C composite anode demonstrates exceptional stability in ether-based electrolytes. This work establishes a paradigm for atomic-level engineering in Li─C composite anodes.