Hollow nanostructured hosts are important scaffolds to achieve high sulfur loading, fast charge transfer, and conspicuous restraint of lithium polysulfides (LiPSs) shuttling in lithium-sulfur (Li-S) batteries. However, developing high-efficiency hollow hosts for improving utilization and conversion of aggregated sulfur in the hollow chamber remains a longstanding challenge. Herein, hollow N-doped carbon nanocubes confined petal-like ZnS/SnS2 heterostructures (ZnS/SnS2 @NC) as a conceptually novel host for Li-S batteries are reported. Specifically, compared to consubstantial hollow double-shelled hosts, the ZnS/SnS2 @NC with higher effective active surface area brings dense contact with sulfur and enhances efficient adsorption sites for binding LiPSs and accelerating their conversion. Benefiting from the unique structure and sophisticated composition, the resulting S@ZnS/SnS2 @NC cathodes exhibit 1294 mAh g-1 at 0.2 C, an ultralow capacity decay of 0.016% per cycle over 500 cycles at 1.0 C, and a high area capacity of 4.77 mAh cm-2 at 0.5 C (5.9 mg cm-2 ). Meanwhile, the performance evolution of S@ZnS/SnS2 @NC cathodes under various sulfur loadings is further investigated by using EIS, which provides the beneficial guidance to explore viable strategies further optimizing their performance. This work sheds new insights into the design of hollow nanostructured hosts with a distinguished ability to regulate LiPSs in Li-S batteries.
Keywords: Li-S batteries; ZnS/SnS 2 heterostructures; high sulfur utilization; hollow nanostructured hosts; reaction kinetics.
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