In this work, the core‐shelled Sb@Sb2O3 heterostructure encapsulated in 3D N‐doped carbon hollow‐spheres is fabricated by spray‐drying combined with heat treatment. The novel core‐shelled heterostructures of Sb@Sb2O3 possess a mass of heterointerfaces, which formed spontaneously at the core‐shell contact via annealing oxidation and can promote the rapid Na+/K+ transfer. The density functional theory calculations revealed the mechanism and significance of Na/K‐storage for the core‐shelled Sb@Sb2O3 heterostructure, which validated that the coupling between the high‐conductivity of Sb and the stability of Sb2O3 can relieve the shortcomings of the individual building blocks, thereby enhancing the Na/K‐storage capacity. Furthermore, the core‐shell structure embedded in the 3D carbon framework with robust structure can further increase the electrode mechanical strength and thus buffer the severe volume changes upon cycling. As a result, such composite architecture exhibited a high specific capacity of ≈573 mA h g−1 for sodium‐ion battery (SIB) anode and ≈474 mA h g−1 for potassium‐ion battery (PIB) anode at 100 mA g−1, and superior rate performance (302 mA h g−1 at 30 A g−1 for SIB anode, while 239 mA h g−1 at 5 A g−1 for PIB anode).

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The development of sodium-ion (SIBs) and potassium-ion batteries (PIBs) has increased rapidly because of the abundant resources and cost-effectiveness of Na and K. Antimony (Sb) plays an important role in SIBs and PIBs because of its high theoretical capacity, proper working voltage, and low cost. However, Sb-based anodes have the drawbacks of large volume changes and weak charge transfer during the charge and discharge processes, thus leading to poor cycling and rapid capacity decay. To address such drawbacks, many strategies and a variety of Sb-based materials have been developed in recent years. This review systematically introduces the recent research progress of a variety of Sb-based anodes for SIBs and PIBs from the perspective of composition selection, preparation technologies, structural characteristics, and energy storage behaviors. Moreover, corresponding examples are presented to illustrate the advantages or disadvantages of these anodes. Finally, we summarize the challenges of the development of Sb-based materials for Na/K-ion batteries and propose potential research directions for their further development.