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SnS_2由于具有较高的储锂容量(645 mAh·g~(-1))、价格低廉等优点而受到研究者的广泛关注。但纯Sn S_2在脱嵌锂过程中存在严重的体积膨胀效应,造成活性物质粉化和剥落,从而导致容量的迅速衰减。针对这一问题,本文采用简单的一步溶剂热法制备了SnS_2纳米花/石墨烯(SnS_2 NF/GNs)纳米复合物。其中花状SnS_2由超薄纳米片组装而成,石墨烯纳米片将SnS_2包裹在其中。将该材料用作锂离子电池负极时,SnS_2 NF/GNs表现出优越的电化学性能,如:循环200圈后可逆容量仍可达523 mAh?g~(-1)复合物材料提高的储锂性能得益于SnS_2和石墨烯的协同效应。纳米结构的SnS_2可以有效的缓冲体积的膨胀,缩短锂离子的扩散距离。石墨烯纳米片不仅可以进一步缓冲SnS_2体积的膨胀,而且可以提高纳米复合物的导电性。
Due to its high lithium storage capacity (645 mAh · g -1) and its low cost, SnS_2 attracts much attention from researchers. However, pure Sn S 2 has a serious volume expansion effect during deintercalation of lithium, resulting in the active material being pulverized and exfoliated, resulting in a rapid capacity decay. In response to this problem, SnS_2 nanocrystals (SnS 2 NF / GNs) nanocomposites were prepared by a simple one-step solvothermal method. Among them, flower-like SnS 2 is assembled by ultra-thin nanosheets, in which SnS 2 is wrapped by graphene nanosheets. The SnS 2 NF / GNs exhibited excellent electrochemical performance when used as a negative electrode for Li-ion batteries, such as the lithium storage capacity increased by 523 mAh? G -1 composite material after 200 cycles Performance benefits from the synergistic effect of SnS_2 and graphene. Nanostructured SnS_2 can effectively buffer the volume expansion and shorten the diffusion distance of lithium ions. Graphene nanosheets can not only further buffer the bulk of SnS_2, but also improve the conductivity of nanocomposites.