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Oxygen doping is an effective strategy for constructing high‐performance carbon anodes in Na ion batteries; however, current oxygen‐doped carbons always exhibit low doping levels and high‐defect surfaces, resulting in limited capacity improvement and low initial Coulombic efficiency (ICE). Herein, a stainless steel‐assisted high‐energy ball milling is exploited to achieve high‐level oxygen doping (19.33%) in the carbon framework. The doped oxygen atoms exist dominantly in the form of carbon‐oxygen double bonds, supplying sufficient Na storage sites through an addition reaction. More importantly, it is unexpected that the random carbon layers on the surface are reconstructed into a quasi‐ordered arrangement by robust mechanical force, which is low‐defect and favorable for suppressing the formation of thick solid electrolyte interfaces. As such, the obtained carbon presents a large reversible capacity of 363 mAh g−1 with a high ICE up to 83.1%. In addition, owing to the surface‐dominated capacity contribution, an ultrafast Na storage is achieved that the capacity remains 139 mAh g−1 under a large current density of 100 A g−1. Such good Na storage performance, especially outstanding rate capability, has rarely been achieved before.

Selenium (Se) is an ideal doping agent to modulate the structure of carbon materials to improve their sodium storage performance but has been rarely investigated. In the present study, a...

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Sulfur (S) doping is an effective method for constructing highperformance carbon anodes for sodium-ion batteries. However, traditional designs of S-doped carbon often exhibit low initial Coulombic efficiency (ICE), poor rate capability, and impoverished cycle performance, limiting their practical applications. This study proposes an innovative design strategy to fabricate Sdoped carbon using sulfonated sugar molecules as precursors via high-energy ball milling. The results show that the high-energy ball milling can immobilize S for sulfonated sugar molecules by modulating the chemical state of S atoms, thereby creating a S-rich carbon framework with a doping level of 15.5 wt %. In addition, the S atoms are present mainly in the form of C−S bonds, facilitating a stable electrochemical reaction; meanwhile, S atoms expand the spacing between carbon layers and contribute sufficient capacitance-type Na-storage sites. Consequently, the S-doped carbon exhibits a large capacity (>600 mAh g −1 ), a high ICE (>90%), superior cycling stability (490 mAh g −1 after 1100 cycles at 5 A g −1 ), and outstanding rate performance (420 mAh g −1 at a high current density of 50 A g −1 ). Such excellent Na-storage properties of S-doped carbon have rarely been reported in the literatures before.