高级检索

基于PDA限制结构 MoS2/PDA/SnS2纳米管的构建及其锂离子电池性能研究

Construction and Lithium-Ion Battery Performance of MoS2/PDA/SnS2 Nanotubes Based on a PDA Confinement Structure

  • 摘要: 二硫化钼(MoS2)与二硫化锡(SnS2)因其较高的理论容量和较宽的层间距,常被用作锂离子电池负极材料,二者复合体系更是当前研究的重点之一。然而,常规的MoS2/SnS2复合结构在电池循环过程中会经历显著的体积膨胀,容易引起电极材料的结构损坏,从而导致比容量快速下降,制约了该类复合材料在电池电极应用中本应具备的循环稳定性能。在这项工作中,设计并合成了一种新型的MoS2/PDA/SnS2纳米管。具体来说,就是在空心MoS2纳米管外面包覆一层PDA作为限制结构,防止后续过程MoS2结构的破碎,随后在PDA表面水热生长一层SnS2纳米片得到MoS2/PDA/SnS2纳米管。这种制备方法不仅防止了中空管状结构的破裂,游离的多巴胺分子还促进了SnS2纳米片的生长。这种优越的结构设计,极大地提高了材料的稳定性,同时也提升了材料的导电性。在用作电极时,该复合材料展现出出色的长循环性能:其在0.1 A g1的电流密度下经过90次循环后,放电比容量仍可达1330.2 mAhg1;即便在1 A g1的大电流条件下持续循环800周,容量仍能稳定在1366.3 mAhg1

     

    Abstract: Molybdenum disulfide (MoS2) and tin disulfide (SnS2), known for their high theoretical capacities and large interlayer spacings, have been widely used as anode materials in lithium-ion batteries. The composite materials formed between them are an even greater research focus. However, conventional MoS2/SnS2 composites suffer from severe volume changes and structural fragmentation during the charge–discharge cycles, leading to rapid decay in specific capacity, which hinders the cycling stability that MoS2/SnS2 composite electrodes should ideally possess. In this work, a novel MoS2/PDA/SnS2 nanotube was designed and synthesized. Specifically, a hollow MoS2 nanotube was coated with a polydopamine (PDA) layer as a confinement structure to prevent the structural breakdown of MoS2 in subsequent processes. Subsequently, MoS2/PDA/SnS2 nanotubes were successfully prepared by growing a layer of SnS2 nanosheets on the polydopamine (PDA) surface through a hydrothermal method. This preparation method not only prevented the rupture of the hollow tubular structure but also facilitated the growth of SnS2 nanosheets through the free dopamine molecules. This superior structural design significantly enhances the stability of the material while also improving its electrical conductivity. The composite electrode demonstrates excellent cyclability, retaining a specific discharge capacity of 1330.2 mAhg1 over 90 cycles at 0.1 A g1. Notably, even after 800 cycles at a high rate of 1 A g1, the capacity remains virtually unchanged at 1366.3 mAhg1.

     

/

返回文章
返回