Lithium-ion batteries (LIBs) with high volume specific capacity have promising applications in small/microelectronics. However, the contradiction between Li⁺ diffusion kinetics and material compaction density severely restricts its development. The layered bismuth selenide (Bi₂Se₃) with high conductivity and compaction density is a candidate material for LIBs with high volume specific capacity. In this work, Bi₂Se₃@C was synthesized by solvothermal and selenization methods, and the final product exhibits a high specific capacity (468 mAh g⁻¹ at 0.1 A g⁻¹, corresponding to 1862 mAh cm⁻³) and good cycling stability (358 mAh g⁻¹ after 500 cycles at 0.5 A g⁻¹, corresponding to 1445 mAh cm⁻³). The excellent electrochemical performance results from the special morphology of the carbon layer-coated Bi₂Se₃ nanospheres, and the carbon layer not only regulates the volume expansion of Bi₂Se₃ during cycling but also improves the electronic conductivity, which is also confirmed by density functional theory calculation. Ex-situ X-ray diffraction spectrum reveals that the crystal phase of Bi₂Se₃ changed from hexagon to orthogonal after the initial cycle.

具有高容量比容量的锂离子电池（LIB）在小型/微电子领域具有广阔的应用前景。^{然而，Li +}扩散动力学与材料压实密度之间的矛盾严重制约了其发展。具有高电导率和压实密度的层状硒化铋（Bi ₂ Se ₃）是具有高体积比容量的LIB的候选材料。在这项工作中，Bi ₂ Se ₃ @C 通过溶剂热法和硒化法合成，最终产物表现出高比容量（0.1 A g -1 时为^{468 mAh g -1}，对应于 1862 mAh cm ^-3）和良好的循环稳定性（358 mAh g^-1在 0.5 A g ^-1下 500 次循环后，对应于 1445 mAh cm ^-3 )。优异的电化学性能源于碳层包覆的Bi ₂ Se ₃纳米球的特殊形态，碳层不仅可以调节Bi ₂ Se ₃在循环过程中的体积膨胀，还可以提高电子电导率，这一点也得到了证实。密度泛函理论计算。异位X射线衍射谱表明Bi ₂ Se ₃的晶相在初始循环后由六方晶相变为正交晶相。