Hierarchical TiO₂/SnO₂ Hollow Spheres Coated with Graphitized Carbon for High-Performance Electrochemical Li-Ion Storage

A self-templated strategy is developed to fabricate hierarchical TiO₂/SnO₂ hollow spheres coated with graphitized carbon (HTSO/GC-HSs) by combined sol–gel processes with hydrothermal treatment and calcination. The as-prepared mesoporous HTSO/GC-HSs present an approximate yolk-double–shell structure, with high specific area and small nanocrystals of TiO₂ and SnO₂, and thus exhibit superior electrochemical reactivity and stability when used as anode materials for Li-ion batteries. A high reversible specific capacity of about 310 mAh g⁻¹ at a high current density of 5 A g⁻¹ can be achieved over 500 cycles indicating very good cycle stability and rate performance.