Walnut-like Porous Core/Shell TiO2 with Hybridized Phases Enabling Fast and Stable Lithium Storage

TiO2 is a promising and safe anode material for lithium ion batteries (LIBs). However, its practical application has been plagued by its poor rate capability and cycling properties. Herein, we successfully demonstrate a novel structured TiO2 anode with excellent rate capability and ultralong cycle life. The TiO2 material reported here shows a walnut-like porous core/shell structure with hybridized anatase/amorphous phases. The effective synergy of the unique walnut-like porous core/shell structure, the phase hybridization with nanoscale coherent heterointerfaces, and the presence of minor catbon species endows the TiO2 material with superior lithium storage properties in terms of high capacity (similar to 177 mA h g(-1) at 1 C, 1 C = 170 mA g(-1)), good rate capability (62 mA h g(-1) at 100 C), and excellent cycling stability (similar to 83 mA h g(-1) was retained over 10 000 cycles at 10 C with a capacity decay of 0.002% per cycle).