Preparation of SnO₂@C/ Reduced Graphene Oxide Nanocomposite as Anode Materials for Lithium-Ion Battery

SnO₂ is widely investigated as one of anode materials for lithium-ion batteries due to its natural abundance, low discharge potential (less than 1.5 V) and high theoretical capacity. However, the low electrical conductivity and large volume expansion (300%) during Li⁺ insertion/extraction results in the poor cyclability and rate capability of SnO₂, thus restricting its practical applications. In this study, SnO₂@C/rGO nanocomposites were prepared by an one-step hydrothermal method with SnCl₂, L-ascorbic acid and GO as reactants. The L-ascorbic acid-derived amorphous carbon served as a spacer to inhibit the stacking of rGO sheets and acted as a coupling agent to strongly anchor SnO₂ nanoparticles on the rGO sheets. The as-obtained SnO₂@C/rGO nanocomposite delivers a specific capacity of 731 mA·h/g after 180 cycles at a current density of 0.1 C (1 C= 783 mA/g) and a high reversible capacity of 410 mA·h/g at a large current rate of 5 C. This study provides a promising route for the preparation of high-performance SnO₂ anode materials.