WS₂-TiO₂ Heterostructure Catalyst for Boosting the Polysulfide Adsorption–Conversion in Lithium–Sulfur Batteries

The introduction of suitable catalytic hosts is considered as a suitable way to hinder the “shuttling effect” of lithium polysulfides (LPSs) in lithium–sulfur (Li–S) batteries. At present, most catalytic hosts can accelerate the conversion of LPSs, but there are few reports that catalytic hosts accelerate the conversion of solid-phase discharge products (Li 2 S 2 /Li 2 S) into liquid-phase LPSs. Herein, a heterostructure catalyst with flaky WS 2 -modified TiO 2 hollow spheres (WS 2 -TiO 2 ) is reported, which accelerates the conversion between liquid-phase LPSs and solid-phase Li 2 S 2 /Li 2 S. A Li–S battery with S@WS 2 -TiO 2 cathode exhibits an initial discharge specific capacity of 1091.7 mAh g –1 at 0.3C, outstanding rate capability of 378.7mAh g –1 at 10C, and low capacity decay of 0.0753% per cycle over 800 cycles at 1C. Therefore, this work provides a suitable way to construct heterosturcture catalytic hosts to realize the commercial application of Li–S batteries.