Nanoconic TiO2 hollow spheres: novel buffers architectured for high-capacity anode materials

An attempt has been carried out here to use nanoconic TiO 2 hollow spheres as buffers to accommodate the volume expansion of high-capacity materials. Based on the TiO 2 hollow spheres, we tailor-designed a novel composite, in which the high Li + -transport dynamics of titanate hollow spheres (TiO 2 ) and the high capacity of tin oxide (SnO 2 ) were intimately integrated into a hierarchical architecture of nanocones, while the unique spatial arrangement of the SnO 2 component in the nano-cavities effectively accommodates the volume change during lithiation/de-lithiation, hence rendering the composite stable cycling life. Electrochemical tests revealed favorable performances of the composite SnO 2 -TiO 2 nanocones in terms of enhanced lithium storage capacity, stable cycle life and improved rate performance compared with each material components. The unique hierarchical structure of SnO 2 -TiO 2 -NC hollow spheres leads to the enhanced lithium storage capacity and stable cycle life.