Synthesis of Si/TiO2 core–shell nanoparticles as anode material for high performance lithium ion batteries

Abstract

We demonstrated that titanium dioxide (TiO2) significantly enhances the reversible capacity of silicon nanoparticles (SiNPs) used as the anode material for lithium ion batteries. The novel silicon and titanium dioxide core–shell nanoparticles (Si/TiO2) was prepared via a facile sol–gel method with the following heat-treatment process. The as-prepared materials were confirmed by X-ray diffraction, Raman spectra and transmission electron microscope. As an anode material for battery, the electrode was investigated by a series of electrochemical measurements. The as-prepared Si/TiO2 electrode exhibits superior electrochemical performance in comparison with pure SiNPs, which realizes an initial capacity as high as 2636.9 mAh/g and still retains 1010.7 mAh/g even after 100 cycles of charging and discharging. The excellent cycle stability and capacity retention of the as-prepared electrode would be attributed to the existence of TiO2 layers to accommodate the large volume changes of silicon and enhancement ability to minimizes loss of pulverization during the lithium insertion/desertion cycles. Therefore, the as-prepared Si/TiO2 is believed to be an potential anode material for lithium-ion battery applications.