Construction of SnS₂-modified multi-hole carbon nanofibers with sulfur encapsulated as free-standing cathode...

Lithium-sulfur (Li-S) batteries exhibit a huge potential in energy storage devices for the thrilling theoretical energy density (2600 Wh kg^-1). Nevertheless, the serious shuttle effect rooted in polysulfides and retardative hysteresis reaction kinetics results in inferior cycling and rate performances of Li-S batteries, impeding commercial applications. In order to further promote the energy storage abilities of Li-S batteries, a unique binder-free sulfur carrier consisting of SnS₂-modified multi-hole carbon nanofibers (SnS₂-MHCNFs) has been constructed, where MHCNFs can offer abundant space to accommodate high-level sulfur and SnS₂can promote the adsorption and catalyst capability of polysulfides, synergistically promoting the lithium-ion storage performances of Li-S batteries. After sulfur loading (SnS₂-MHCNFs@S), the material was directly applied as a cathode electrode of the Li-S battery. The SnS₂-MHCNFs@S electrode maintained a good discharge capacity of 921 mAh g^-1after 150 cycles when the current density was 0.1 C (1 C = 1675 mA g^-1), outdistancing the MHCNFs@S (629 mAh g^-1) and CNFs@S (249 mAh g^-1) electrodes. Meanwhile, the SnS₂-MHCNFs@S electrode still exhibited a discharge capacity of 444 mAh g^-1at 2 C. The good performance of SnS₂-MHCNFs@S electrode indicates that combining multihole structure designation and polar material modification are highly effective methods to boost the performances of Li-S batteries.