Materials with alloying reactions have significant potential as electrodes for lithium-ion batteries (LIBs) due to its high theoretical capacity and appropriate lithiation potentials. Nonetheless, their cycling performance is inferior due to violent volume expansion and severe pulverization of active materials. Herein, solid solution of Bi_0.5Sb_0.5 encapsulated with carbon is discovered to enable consecutive alloying reactions with manageable volume change, suitable for developing LIBs with high capacity and robust cyclability. A Sb-rich shell and Bi-rich core structure is formed in cycling since the alloying reaction between Sb and Li occurs first, followed by the alloying reaction between Bi and Li. Such a consecutive alloying reaction obeying the thermodynamic path is experimentally realized by the carbon capsulation, which acts as a protecting solid layer to avoid polarized reactions occurred when exposed directly to liquid electrolyte. The LIBs using Bi_0.5Sb_0.5@carbon run on the consecutive alloying reactions exhibits high capacity, prolonged lifespan (489.4 mAh g⁻¹ after 2000 cycles at 1 A g⁻¹) and fast kinetic, while those using bare Bi_0.5Sb_0.5 suffer from worsened kinetic and thus a poor cycling performance owning to the polarized reactions. The work paves a way of developing alloy electrodes for alkaline-ion rechargeable batteries with potential industry applications.

中文翻译：

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Bi 和 Sb 的固溶体通过连续合金化反应实现稳健的锂存储

由于具有高理论容量和适当的锂化电位，具有合金化反应的材料具有作为锂离子电池（LIBs）电极的巨大潜力。尽管如此，由于剧烈的体积膨胀和活性材料的严重粉化，它们的循环性能较差。在此，Bi _0.5 Sb _{0.5 的}固溶体发现用碳包封可以使连续的合金化反应具有可控的体积变化，适用于开发具有高容量和强大循环能力的 LIB。由于首先发生 Sb 和 Li 之间的合金化反应，然后是 Bi 和 Li 之间的合金化反应，因此在循环过程中形成了富 Sb 壳和富 Bi 核结构。这种遵循热力学路径的连续合金化反应是通过碳封装实验实现的，碳封装充当保护固体层，以避免在直接暴露于液体电解质时发生极化反应。使用 Bi _0.5 Sb _0.5 @carbon 在连续合金化反应中运行的 LIB 表现出高容量、延长的寿命（在 1 A g 下循环 2000 次后为489.4 mAh g ^-1-1 ) 和快速动力学，而那些使用裸 Bi _0.5 Sb _{0.5 的}动力学恶化，因此由于极化反应而导致循环性能差。这项工作为开发具有潜在工业应用的碱性离子充电电池的合金电极铺平了道路。