Hydrothermal Synthesis of Li₄Ti₅O₁₂/TiO₂ Nano-composite As High Performance Anode Material for Li-Ion Batteries

Highlights: • Dual phase Li₄Ti5O₁₂/TiO₂ nano-composite is synthesized by a gacilehydrothermal approach. • The dual phase formation mechanism is proposed by the inhomogeneous Li distribution. • The phase composition can be tuned by the solution composition. - Abstract: A facile hydrothermal approach has been developed to synthesize the nanostructured dual phase Li₄Ti₅O₁₂/TiO₂ composite. The fabrication process simply involves the hydrothermal treatment of tetrabutyl titanate with LiOH in glycerol-water solution and a subsequent calcination procedure. The calcination treatment at 500 °C leads to the phase evolution from Li_1.81H_0.19Ti₂O₅• nH₂O to Li₄Ti₅O₁₂/TiO₂ composite with a particle size of about 30 nm. It is found that glycerol as chelating agent plays an important role in the formation of TiO₂. The Li₄Ti₅O₁₂ and anatase TiO₂ nano-composite exhibits rich hierarchical pores and a specific surface area of 91.88 m² g⁻¹, delivers ultrahigh rate performance of over 150 mA h g⁻¹ at 20 C, as well as superior capacity retention of 151.4 mAh g⁻¹ after 100 cycles at 1 C. It is therefore concluded that Li₄Ti₅O₁₂/TiO₂ nano-composite is a promising candidate for applications in high rate lithium ion batteries