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.