Zinc borates have merits of low voltage polarization and suitable redox potential, but usually suffer from low rate capability and poor cycling life, as an emerging anode candidate for Na⁺ storage. Here, a new intercalator-guided synthesis strategy is reported to simultaneously improve rate capability and stabilize cycling life of N, B co-doped carbon/zinc borates (CBZG). The strategy relies on a uniform dispersion of precursors and simultaneously stimulated combustion activation and solid-state reactions capable of scalable preparation. The Na⁺ storage mechanism of CBZG is studied: 1) ex situ XRD and XPS demonstrate two-step reaction sequence of Na⁺ storage: Zn₆ O(OH)(BO₃ )₃ +Na⁺ +e^- ↔3ZnO+Zn₃ B₂ O₆ +NaBO₂ +0.5H₂ ①, Zn₃ B₂ O₆ +6Na⁺ +6e^- ↔3Zn+3Na₂ O+B₂ O₃ ②; reaction ① is irreversible in ether-based electrolyte while reversible in ester-based electrolyte. 2) Electrochemical kinetics reveal that ether-based electrolyte possesses faster Na⁺ storage than ester-based electrolyte. The composite demonstrates an excellent capacity of 437.4 mAh g^-1 in a half-cell, together with application potential in full cells (discharge capacity of 440.1 mAh g^-1 and stable cycle performance of 2000 cycles at 5 A g^-1 ). These studies will undoubtedly provide an avenue for developing novel synthetic methods of carbon-based borates and give new insights into the mechanism of Na⁺ storage in ether-based electrolyte for the desirable sodium storage.

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