First-principles study on S and N doping graphene/SnS2 heterostructure for lithium-ion battery

Abstract Graphene/SnS2 anode Lithium-ion battery (LIB) was reported with high energy capacity (initial capacities over 1500 mAh g−1), long cycle life (532 mAh g−1 after 600 cycles), and high rate performance (844 mAh g−1 at 10A g−1). The enhancement is due to the advantages of composite materials. However, the deeply dynamic mechanism remains undiscussed. Here using first-principles calculation and climbing image nudged elastic band method, we explored this question in the view of adsorption and diffusion, including the effect of defects in graphene and graphene/SnS2 and the low diffusion energy (0.21 eV) and high capacity (~1367 mAh g−1) brought by S and N doping.