Preparation and characterization of SiO2/C nanocomposites by a combination of mechanochemical-assisted sol–gel and dry ball milling processes

• SiO2/C nanocomposites were prepared by a novel preparation technique.
• The nanocomposites consisted of dispersed carbon nanoparticles on SiO2 particles.
• The nanocomposite as electrode active material delivered 653 mA h g−1 at 46 mA g−1.
• The electrode exhibited excellent cyclability over 30 cycles.

A novel preparation route was developed for synthesizing SiO2/C nanocomposites through a mechanochemical-assisted sol–gel process combined with a high-energy dry ball milling process. The effect of process parameters, such as milling time, rotation speed and carbon content, on the structure and morphology of SiO2/C nanocomposites was investigated by X-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy and transmission electron microscopy with energy-dispersive spectroscopy. It was demonstrated from the physical characterization that the proposed preparation route might be an effective synthesis route for SiO2/C nanocomposites consisting of highly dispersed carbon nanoparticles on fine amorphous SiO2 particles. The electrochemical performance was characterized using Li|1 M LiPF6 in EC:DMC = 1:1| SiO2/C cells in the potential range from 0.01 to 3.0 V versus Li/Li+. The SiO2/C nanocomposite prepared under optimized process conditions exhibited a highly stable reversible capacity of 663 mA h g−1(872 mA h g-SiO2−1) at a current density of 46 mA g−1 after 30 cycles with no capacity fading.

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