Self-assembled vapor-liquid-solid growth of aligned Cu-SiO2 core-shell nanocable arrays on Cu substrates

The Cu-SiO2 core-shell nanocable arrays on the Cu wafers have been synthesized via a simple thermal evaporation of the SiO powder. The morphology and structure of the as-synthesized Cu-SiO2 core-shell nanocables are characterized by using scanning electron microscopy, high-resolution transmission electron microscopy, and X-ray energy dispersive spectrometer. The growth of amorphous SiO2 shell follows a vapor-liquid-solid mechanism, and then molten metal Cu will be diffused into the SiO2 nanotubes, forming the Cu-SiO2 core-shell nanocable arrays. It is found that the aligned Cu-SiO2 core-shell nanocables prefer to grow along the grooves of the Cu substrate, and the density of the Cu-SiO2 core-shell nanocable arrays can be controlled by adjusting the growth temperature.