Antimony nanoparticles encapsulated in three-dimensional porous carbon frameworks for high-performance rechargeable batteries

Antimony (Sb) is regarded as a potential candidate for next-generation anode materials for rechargeable batteries because it has a high theoretical specific capacity, excellent conductivity and appropriate reaction potential. However, Sb-based anodes suffer from severe volume expansion of > 135% during the lithiation–delithiation process. Hence, we construct a novel Sb@C composite encapsulating the Sb nanoparticles into highly conductive three-dimensional porous carbon frameworks via the one-step magnesiothermic reduction (MR). The porous carbon provides buffer spaces to accommodate the volume expansion of Sb. Meanwhile, the three-dimensional (3D) interconnected carbon frameworks shorten the ion/electron transport pathway and inhibit the overgrowth of unstable solid-electrolyte interfaces (SEIs). Consequently, the 3D Sb@C composite displays remarkable electrochemical performance, including a high average Coulombic efficiency (CE) of > 99%, high initial capability of 989 mAh·g⁻¹, excellent cycling stability for over 1000 cycles at a high current density of 5 A·g⁻¹. Furthermore, employing a similar approach, this 3D Sb@C design paradigm holds promise for broader applications across fast-charging and ultralong-life battery systems beyond Li⁺. This work aims to advance practical applications for Sb-based anodes in next-generation batteries.

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