Few-layer WS₂ nanosheets with oxygen-incorporated defect-sulphur entrapped by a hierarchical N, S co-doped graphene...

Tungsten sulfide (WS₂) with two-dimensional layered graphene-like structure as an anode for lithium-ion batteries (LIBs) has attracted large attention owing to its high theoretical capacity and unique S-W-S layer structure. However, it also always suffers from poor electrical conductivity and volume expansion during lithiation/delithiation process in the practical application. Herein, we demonstrate the successful synergistic regulation of both structural and electronic modulation by simultaneous oxygen incorporation in defect-sulphur WS₂ nanosheets embedded into a conductive nitrogen and sulfur co-doped graphene framework (denoted as O-DS-WS₂/NSG), leading to dramatically enhanced lithium storage. Such a unique structure not only increases the accessible active sites for Li⁺ and enhances the kinetics of ion/electron transport, but also relieves the volume effect of WS₂. Furthermore, the surface defects and heteroatom incorporation can effectively regulate the electronic structure, improve the intrinsic conductivity and offer more active sites. Consequently, electrochemical performance results demonstrate that the obtained O-DS-WS₂/NSG nanocomposites possess great application prospects in LIBs with high specific capacity, superior rate performance as well as excellent cycle stability.