Chestnut-like SnO2/C nanocomposites with enhanced lithium ion storage properties

Chestnut-like SnO 2 and SnO 2 /C nanocomposites with hierarchical structures are synthesized by hydrothermally oxidizing Sn nanoparticles in glucose solution. Structural characterizations using SEM and TEM reveal that the SnO 2 nanoparticles are composed of numerous, randomly arranged SnO 2 nanosheets with hollow cores. Owing to the short electron and ion diffusion distances and transformation strain accommodation mechanism of this structure the new SnO 2 /C nanocomposites exhibit enhanced lithium ion storage properties with a capacity of ~930   mAh   g −1 and capacity retention of about 96% after 100 cycles at 0.1   C. An in situ TEM study of the electrochemically driven lithiation/delithiation of SnO 2 /C nanocomposites reveals that their enhanced cycling stability is mainly facilitated by the limited volume expansion and excellent mechanical robustness of the hollow chestnuts.