Facile synthesis of Si-C nanocomposites with yolk-shell structure as an anode for lithium-ion batteries

A yolk-shell structured Si-based anode is synthesized by depositing MgO, instead of SiO2, as sacrifice layer and CVD process. Thus the HF etching can be substituted by using diluted HCl, which is less toxic and corrosive. The results show the yolk-shell structure is successfully synthesized and has an improved electrochemistry performance. The amount of MgO coating also has been investigated. The proper mass ratio of MgO and Si can be approx. 2 and a reversible charge capacity of 901 mAh g−1 and 88.3% retention was achieved after 100 cycles at 1.0 A g−1. The significant improvements for cycle performance demonstrate the yolk-shell structured Si-C nanocomposite in this work is a promising anode material for lithium-ion batteries.