Based on the first-principles study, the adsorption and electron transfer properties of Li atom at different sites of SnS₂ monolayer, SnS₂@Graphene 2D-nanocomposite are analyzed. The differential charge density and density of states (DOS) analysis show that the graphene substrate as an electron donor can change the 2D-nanocomposite from a semiconductor to a metal, and reduce the adsorption energy of Li atom by decreasing the charge transferring from Li atom to SnS₂. This indicates that graphene substrate is beneficial for improving the performance of SnS₂@Graphene. Meanwhile, the Li atoms tend not to cluster on the SnS₂@Graphene 2D-nanocomposite, which is useful to prolong the lifespan of the SnS₂@Graphene. The functionality of graphene in SnS₂@Graphene 2D-nanocomposite is proved by other electron donor substrates, such as a two-H-atom model and a Sn (111) substrate model. All the results indicate that the graphene, as an electron donor in SnS₂@Graphene 2D-nanocomposite, plays a key role in improving the performance of SnS₂ in rechargeable lithium batteries.

基于第一性原理研究，分析了SnS ₂单层、SnS ₂ @Graphene 2D纳米复合材料不同位点的Li原子吸附和电子传输特性。差分电荷密度和态密度（DOS）分析表明，石墨烯基底作为电子给体可以将二维纳米复合材料从半导体转变为金属，并通过减少从Li原子转移的电荷来降低Li原子的吸附能至SnS ₂。这表明石墨烯基底有利于提高SnS ₂ @Graphene的性能。同时，Li原子往往不会聚集在SnS ₂ @Graphene 2D纳米复合材料上，这有助于延长SnS ₂ @Graphene的寿命。 SnS ₂ @Graphene 2D 纳米复合材料中石墨烯的功能性已通过其他电子供体基底（例如二氢原子模型和 Sn (111) 基底模型）得到证明。所有结果表明，石墨烯作为SnS _{2 @Graphene 2D纳米复合材料中的电子给体，在提高SnS 2}在可充电锂电池中的性能方面发挥着关键作用。