Solvothermal alcoholysis synthesis of hierarchically porous TiO2-carbon tubular composites as high-performance anodes for lithium-ion batteries

Abstract

Hierarchically porous one-dimensional (1D) TiO2-carbon tubular composites (TiO2C-Ts) with interconnected nanoflakes on the porous tube walls, have been successfully created using a simple solvothermal alcoholysis followed by a subsequent calcination process. The as-prepared TiO2C-Ts demonstrate high electrical conductivity due to the 1D tubular frameworks and the interconnected porous tube walls, offering fast ion/electron transport paths and large space for storing the electrolyte, while buffering the volume change during the Li+ insertion/extraction process. When evaluated as an anode in a lithium-ion battery, the optimized TiO2C-Ts600 electrode displays a remarkable reversible capacity of 534 mA h g−1 after 100 cycles at 180 mA g−1 and an impressive capacity of 284.9 mA h g−1 (∼80% capacity retention) after 3000 cycles at 3.5 A g−1. Further, the performance of the TiO2C-Ts600 electrode is also investigated in a full cell using LiFePO4 as the cathode, demonstrating highly reversible discharge capacity (353.8 mA h g−1 after 100 cycles at 100 mA g−1, corresponding to capacity retention of ∼73%) and superior rate capability (254.4 mA h g−1 at 1.0 A g−1), suggesting its great potential application in high-performance energy storage devices.