Liu Huiqiao, He Yanan, Zhang Hang, Wang Shaodan, Cao Kangzhe, Jiang Yong, Liu Xiaogang, Jing Qiang-Shan
College of Chemistry and Chemical Engineering, Henan Province Key Laboratory of Utilization of Non-Metallic Mineral in the South of Henan, Xinyang Normal University, Xinyang 464000, China.
College of Chemistry and Chemical Engineering, Henan Province Key Laboratory of Utilization of Non-Metallic Mineral in the South of Henan, Xinyang Normal University, Xinyang 464000, China.
J Colloid Interface Sci. 2022 Jan 15;606(Pt 1):167-176. doi: 10.1016/j.jcis.2021.07.146. Epub 2021 Aug 2.
Layered metal sulfides are considered as promising candidates for potassium ion batteries (KIBs) owing to the unique interlayer passages for ion diffusion. However, the insufficient electronic conductivity, inevitable volume expansion, and sulfur loss hinder the promotion of K-ion storage performance. Herein, few-layered TiCT nanosheets were selected as the multi-functional substrate for cooperating few-layered SnS nanosheets, constructing SnS/TiCT hetero-structural nanosheets (HNs) with the thickness as thin as about 5 nm. In this configuration, the formed Ti-S bonds provide robust interaction between SnS and TiCT nanosheets, which hinders the agglomeration of SnS and the restack of TiCT, endowing the hybrid material with robust nanostructure. Thus, the shortcomings of the SnS anode are muchly relieved. In this way, the as-prepared SnS/TiCT HNs electrode delivers reversible capacities of 462.1 mAh g at 0.1 A g and 166.1 mAh g at 2.0 A g, respectively, and a capacity of 85.5 mAh g is remained even after 460 cycles at 2.0 A g. These results are superior to those of the counterpart electrode, confirming aggressive promotion of K-ion storage performance of SnS anode brought by the cooperation of TiCT, and presenting a reliable strategy to improve the electrochemical performance of sulfide anodes.
层状金属硫化物因其独特的离子扩散层间通道而被认为是钾离子电池（KIBs）的有潜力的候选材料。然而，电子导电性不足、不可避免的体积膨胀和硫损失阻碍了钾离子存储性能的提升。在此，选择少层TiCT纳米片作为多功能基底，与少层SnS纳米片协同作用，构建厚度约为5nm的SnS/TiCT异质结构纳米片（HNs）。在这种结构中，形成的Ti-S键在SnS和TiCT纳米片之间提供了强大的相互作用，这阻碍了SnS的团聚和TiCT的重新堆叠，赋予了混合材料坚固的纳米结构。因此，SnS负极的缺点得到了很大程度的缓解。通过这种方式，所制备的SnS/TiCT HNs电极在0.1 A g时的可逆容量分别为462.1 mAh g，在2.0 A g时为166.1 mAh g，即使在2.0 A g下循环460次后仍保持85.5 mAh g的容量。这些结果优于相应电极，证实了TiCT的协同作用对SnS负极钾离子存储性能的积极促进作用，并提出了一种提高硫化物负极电化学性能的可靠策略。
