Preparation and electrochemical properties of TiO2/C/Si composites for lithium ion batteries

• TiO2/C/Si composite was synthesized by a simple hydrothermal method.
• The TiO2/C/Si composite exhibits enhanced electrochemical performances.
• The improvement can be attributed to the synergy effect of carbon and TiO2.

TiO2, C/Si and TiO2/C/Si composite materials are synthesized with a simple hydrothermal method as anode materials for lithium ion batteries (LIBs). X-ray diffraction (XRD), Raman spectroscopy and field-emission scanning electron microscopy (FESEM) reveal that composite with C and TiO2 does not influence the crystal structure of pristine Si. It is found that the TiO2/C/Si composite exhibits enhanced capacity retention and excellent rate capability compared with Si, TiO2 and C/Si composite. The composite delivers a high capacity of 861 mA h g−1 at 0.1 C after 50 cycles. Even at high current density, the TiO2/C/Si composite still demonstrates good cycling stability. The improvement in electrochemical performances can be attributed to the synergy effect of carbon and TiO2, in which the carbon mixed naturally enhances the electrical conductivity and the TiO2 outside effectively suppresses the volume change of Si particles.