Improved catalytic conversion of polysulfide by MoO2/C composite host for stable Li–S batteries

Lithium-sulfur batteries with high theoretical energy density have drawn much attention during the past decades, while the shuttle effect of the polysulfide also hinders the practical application. The employment of suitable host materials has been considered as the effective strategy to inhibit the polysulfide migration. In this work, we develop MoO 2 /C composite as sulfur host material to increase the capacity of lithium-sulfur batteries while retaining high capacity after cycles. The MoO 2 /C composite could serves as active sites, effectively adsorbing and catalytically converting polysulfide, thus improving the redox kinetics and reducing shuttle effect. Owing to these merits, the as-prepared MoO 2 /C@S cathodes exhibit high capacity of 1165 mAh g −1 at 0.1 C. Meanwhile, the battery exhibits superior rate capability and stable cycling performance.