Hierarchical SnO2 nanoflowers assembled by atomic thickness nanosheets as anode material for lithium ion battery

Hierarchical SnO2 nanoflowers assembled by atomic thickness nanosheets were prepared by facile one-pot solvothermal method with acetone/water mixture as solvent. The crystal structure, morphology and the microstructure of the as-prepared products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and atomic force microscope (AFM). Results revealed that the nanoflowers (2-4 μm) were assembled by the ultrathin SnO2 nanosheets (3.1 nm estimated by AFM). When tested as anode material for lithium ion batteries, the SnO2 nanoflowers showed improved cycling stability comparing with the commercial SnO2 particles. The reversible charge capacity of SnO2 nanoflowers maintained 350.7 mAh/g after 30 cycles, while that of the commercial SnO2 was only 112.2 mAh/g. The high reversible capacity and good cycling stability could be ascribed to the hierarchical nanostructure, atomic thickness nanosheets and large surface area of the SnO2 nanoflowers.