Hollow core–shell-structured Si–C composites as high-performance anodes for lithium-ion batteries

Abstract

Hollow core–shell-structured SiO@void@C composites were synthesized by chemical vapor deposition with acetylene gas, and they could be applied as anode materials for lithium ion (Li-ion) batteries. In addition, this structure was designed to accommodate the volume expansion during lithiation for high-performance Li-ion battery anodes. The structures and morphologies of the synthesized composites were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), from which an egg-like structure was observed due to the deposition of carbon layers on the SiO surface. A void space between the particles and the shell was formed as well. The electrochemical tests of the as-prepared samples indicated that high capacity (1780mAh/g at first cycle) and high Coulombic efficiency (50 cycles with 99.84%) were achieved in this core–shell structured SiO electrode. Therefore, the core–shell SiO/C nanocomposite exhibits better electrochemical performance than pure SiO nanoparticles, indicating that it is a promising material to improve the cyclability and kinetics of nano-anode materials for Li-ion batteries.