Porous TiO2/C Nanocomposite Shells As a High-Performance Anode Material for Lithium-Ion Batteries

Porous TiO2/C nanocomposite shells with high capacity, excellent cycle stability, and rate performance have been prepared. The synthesis involves coating colloidal TiO2 nanoshells with a resorcinol-formaldehyde (RE) layer with controllable thickness through a sol-gellike process, and calcining the composites at 700 degrees C in an inert atmosphere to induce crystallization from amorphous TiO2 to anatase and simultaneous carbonization from RE to carbon. The cross-linked RE polymer contributes to the high stability of the shell morphology and the porous nature of the shells. A strong dependence of the capacity on the amount of incorporated carbon has been revealed, allowing the optimization of the electrode structure for high-rate cell performance.