SnO₂ Quantum Dots@Graphene Framework as a High-Performance Flexible Anode Electrode for Lithium-Ion Batteries

Abstract

Three-dimensional (3D) layered tin oxide quantum dots/graphene framework (SnO₂ QDs@GF) were designed through anchoring SnO₂ QD on the graphene surface under the hydrothermal reaction. SnO₂ QDs@GF have a 3D skeleton with a large number of mesopores and ultrasmall SnO₂ QDs with a large surface area. The unique design of this structure improves the specific area and promotes ion transport. The mechanically strong SnO₂ QDs@GF can directly be used as the anode of lithium-ion batteries (LIBs); it displays a high reversible capacity (1300 mA h g^-1 at 100 mA g^-1), excellent rate performance (642 mA h g^-1 at 2000 mA g^-1), and superior cyclic stability (when the current density is 10 A g^-1, the capacity loss is less than 2% after 5000 cycles). This novel synthetic method can further be expanded for the production of other quantum dots/graphene composites with a 3D structure as high-performance electrodes for LIBs.