High initial coulombic efficiency is highly desired because it implies effective interface construction and few electrolyte consumption, indicating enhanced batteries life and power output. In this work, ah igh-capacity sodium storage material with FeS 2 nanoclusters ( % 1-2 nm) embedded in N, Sdoped carbon matrix (FeS 2 /N,S-C) was synthesized, the surface of which displays defects-repaired characteristic and detectable dot-matrix distributed Fe-N-C/Fe-S-C bonds.A fter the initial discharging process,t he uniform ultra-thin NaF-rich ( % 6.0 nm) solid electrolyte interphase was obtained, thereby achieving verifiable ultra-high initial coulombic efficiency ( % 92 %). The defects-repaired surface provides perfect platform, and the catalysis of dot-matrix distributed Fe-N-C/Fe-S-Cb onds to the rapid decomposing of NaSO 3 CF 3 and diethylene glycol dimethyl ether successfully accelerate the building of two-dimensional ultra-thin solid electrolyte interphase.D FT calculations further confirmed the catalysis mechanism. As ar esult, the constructed FeS 2 /N,S-C provides high reversible capacity (749.6 mAh g À1 at 0.1 Ag À1 )a nd outstanding cycle stability (92.7 %, 10 000 cycles,1 0.0 Ag À1 ). Especially,a tÀ15 8 8C, it also obtains ar eversible capacity of 211.7 mAh g À1 at 10.0 Ag À1 .A ssembled pouch-type cell performs potential application. The insight in this work provides abright way to interface design for performance improvement in batteries.

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High initial coulombic efficiency is highly desired because it implies effective interface construction and few electrolyte consumption, indicating enhanced batteries life and power output. In this work, ah igh-capacity sodium storage material with FeS 2 nanoclusters ( % 1-2 nm) embedded in N, Sdoped carbon matrix (FeS 2 /N,S-C) was synthesized, the surface of which displays defects-repaired characteristic and detectable dot-matrix distributed Fe-N-C/Fe-S-C bonds.A fter the initial discharging process,t he uniform ultra-thin NaF-rich ( % 6.0 nm) solid electrolyte interphase was obtained, thereby achieving verifiable ultra-high initial coulombic efficiency ( % 92 %). The defects-repaired surface provides perfect platform, and the catalysis of dot-matrix distributed Fe-N-C/Fe-S-Cb onds to the rapid decomposing of NaSO 3 CF 3 and diethylene glycol dimethyl ether successfully accelerate the building of two-dimensional ultra-thin solid electrolyte interphase.D FT calculations further confirmed the catalysis mechanism. As ar esult, the constructed FeS 2 /N,S-C provides high reversible capacity (749.6 mAh g À1 at 0.1 Ag À1 )a nd outstanding cycle stability (92.7 %, 10 000 cycles,1 0.0 Ag À1 ). Especially,a tÀ15 8 8C, it also obtains ar eversible capacity of 211.7 mAh g À1 at 10.0 Ag À1 .A ssembled pouch-type cell performs potential application. The insight in this work provides abright way to interface design for performance improvement in batteries.

Phosphorus exhibits high capacity and low redox potential, making it a promising anode material for future sodium‐ion batteries. However, its practical applications are confined by poor durability and sluggish kinetics. Herein, an innovative in‐situ electrochemically self‐driven strategy is presented to embed phosphorus nanocrystal (≈10 nm) into a Fe‐N‐C‐rich 3D carbon framework (P/Fe‐N‐C). This strategy enables rapid and high‐capacity sodium ion storage. Through a combination of experimental assistance and theoretical calculations, a novel synergistic catalytic mechanism of Fe‐N‐C is reasonably proposed. In detail, the electrochemical formation of Fe‐N‐C catalytic sites facilitates the release of fluorine in ester‐based electrolyte, inducing Na+‐conducting‐enhanced solid‐electrolyte interphase. Furthermore, it also effectively induces the dissociation energy of the P‐P bond and promotes the reaction kinetics of P anode. As a result, the unconventional P/Fe‐N‐C anode demonstrates outstanding rate‐capability (267 mAh g−1 at 100 A g−1) and cycling stability (72%, 10 000 cycles). Notably, the assembled pouch cell achieves high‐energy density of 220 Wh kg−1.

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