Lithium-sulfur (Li-S) batteries have been recognized as outstanding candidates for energy storage systems due to their superiority in terms of energy density. To meet the requirements for practical use, it is necessary to develop an effective method to realize Li-S batteries with high sulfur utilization and cycle stability. Here, a strategy to construct heterostructure composites as cathodes for high performance Li-S batteries is presented. Taking the SnS2 /SnO2 couple as an example, SnS2 /SnO2 nanosheet heterostructures on carbon nanofibers (CNFs), named C@SnS2 /SnO2 , were designed and synthesized. Considering the electrochemical performance of SnS2 /SnO2 heterostructures, it is interesting to note that the existence of heterointerfaces could efficiently improve lithium ion diffusion rate so as to accelerate the redox reaction significantly, thus leading to the enhanced sulfur utilization and more excellent rate performance. Benefiting from the unique structure and heterointerfaces of C@SnS2 /SnO2 materials, the battery exhibited excellent cyclic stability and high sulfur utilization. This work may provide a powerful strategy for guiding the design of sulfur hosts from selecting the material composition to constructing of microstructure.
Keywords: Catalysis; electrochemistry; heterojunction; interfacial effect; lithium-sulfur batteries.
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