High-Performance and Reactivation Characteristics of High-Quality, Graphene-Supported SnS₂ Heterojunctions for a Lithium-Ion Battery Anode

SnS₂ has received tremendous attention as an anode material for lithium-ion batteries owing to its high theoretical capacity and low cost. However, its applications are limited by its inferior cycling stability and poor rate performance. In this study, graphene@SnS₂ heterojunction nanocomposites are synthesized using a microwave-assisted solvothermal approach on liquid-phase exfoliated graphene (LEGr). Compared with graphene oxides, LEGr layers with an intrinsic atomic structure show extraordinary conductivity and serve as robust substrates for in situ growth of SnS₂ with improved interfacial contact. A LEGr-derived SnS₂ hybrid shows remarkable storage capacity, superior rate capability, and excellent cycling stability. The storage capacity remains at 664 mAh g^-1 after 200 cycles at 300 mA g^-1 current density. Furthermore, lithiation-induced reactivation of LEGr-based SnS₂ is investigated using in situ transmission electron microscopy, giving an in-depth explanation of the electrochemical reaction mechanisms.