Enhanced conductive core–shell structured Si/Ag@SiOx particles as high performance anode material for lithium ion batteries

Abstract In this research, silver-embedded silicon@silica (Si/Ag@SiOx) was successfully fabricated. The Ag nanoparticles were deposited on the surface of Si-core particles by self-selective electroless deposition, then SiOx-shell was generated by wet oxidation in a sealed Teflon-lined autoclave. With the aid of embedded-Ag nanoparticles, the powder resistivity of Si/Ag@SiOx is only 0.747 kΩ·cm, which is nearly 3.42 × 104 times lower than that of silicon@silica (Si@SiOx). Benefiting from the double effects of SiOx-shell (mechanical buffering) and embedded-Ag (high electric conductivity), Si/Ag@SiOx presents excellent electrochemical performance as anode material for lithium ion batteries. The discharge capacity of Si/Ag@SiOx is up to 1453.2 mAh g−1 after 100 cycles. Besides, Si/Ag@SiOx holds 334.8 mAh g−1 higher capacity than Si@SiOx at current density of 8.4 A g−1 (2 C), which is attributed to rapid electron transport brought by the embedded-Ag nanoparticles.