Pan Anqiang

Rational synthesis of SnS 2 @C hollow microspheres with superior stability for lithium-ion batteries

Tin-based nanomaterials have been extensively explored as high-capacity anode materials for lithium ion batteries (LIBs). However, the large volume changes upon repeated cycling always cause the pulverization of the electrode materials. Herein, we report the fabrication of uniform SnS2@C hollow microspheres from hydrothermally prepared SnO2@C hollow microspheres by a solid-state sulfurization process. The as-prepared hollow SnS2@C microspheres with unique carbon shell, as electrodes in LIBs, exhibit high reversible capacity of 814 mA h g−1 at a current density of 100 mA g−1, good cycling performance (783 mA h g−1 for 200 cycles maintained with an average degradation rate of 0.02% per cycle) and remarkable rate capability (reversible cap-abilities of 433 mA h g−1 at 2 C). The hollow space could serve as extra space for volume expansion during the charge-discharge cycling, while the carbon shell can ensure the structural integrity of the microspheres. The preeminent electrochemical performances of the SnS2@C electrodes demonstrate their promising application as anode materials in the next-generation LIBs.摘要锡基材料作为锂离子电池高容量负极材料得到了广泛研究. 然而循环充放电过程中的大体积变化通常会造成电极材料粉化. 本文报道了水热法合成SnO2@C空心微米球, 再对其进行固相硫化制备SnS2@C空心微米球的方法. 制得的SnS2@C空心微米球具有独特的碳外壳及空心结构, 用作锂离子电池电极材料时, 在100 mA g-1电流密度下表现出814 mA h g−1的高可逆容量, 优秀的循环性能(循环200圏后仍保留783 mA h g−1, 平均每圏损失0.02%), 以及出色的倍率容量(2 C时为433 mA h g−1). 其内部空心部分可为充放电循环过程中的体积膨胀提供额外空间, 同时碳外壳能够保护微米球的完整性. 该SnS2@C出色的电化学性能展示出用于下一代锂离子电池负极材料的应用前景.