Freezing Atomic Ion Pumps via Spatiotemporally Decoupled Non‐Equilibrium Engineering of Hard Carbon for Sodium Storage

ABSTRACT

Hard carbon anodes for sodium‐ion batteries are limited by equilibrium carbonization, which imposes a trade‐off between closed‐pore capacity and lattice‐shrinkage‐induced kinetic sluggishness. Herein, a non‐equilibrium spatiotemporally decoupled atomic catalysis was developed by precisely programming the flash Joule heating. Featuring atomically dispersed Mn‐N ₄ sites within the biomass‐derived hard carbon, transient thermal shock simultaneously fuses Mn‐templated micropores into a developed closed‐pore network while freezing Mn atoms to prevent agglomeration. Such a coordination‐mediated structural stabilization effect contributes to the retention of expanded interlayer spacing and mitigating excessive lattice contraction. Additionally, Mn‐N ₄ sites lower the dissociation barrier of electrolyte for forming a robust NaF‐rich solid electrolyte interphase and suppressing solvent co‐intercalation. Theoretical calculations reveal pronounced charge redistribution around Mn‐N ₄ sites, accompanied by a reduced Na ⁺ migration barrier. The induced local electronic polarization, in concert with the optimized interlayer structure, facilitates efficient bulk Na ⁺ transport. The resulting anode delivers high capacity of 439.4 mAh g ⁻¹ and ultralong cycling, with a high energy density of 272.7 Wh kg ⁻¹ in full cell and a power density of 4.56 kW kg ⁻¹ . This work establishes a non‐equilibrium design paradigm in which single atoms act as structural regulators, extending atomic engineering from interfacial modulation to bulk microstructural control of carbon anode.