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

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.