Large-scale synthesis of β-SiC/SiOx coaxial nanocables by chemical vapor reaction approach

Large quantities of β-SiC/SiOx coaxial nanocables have been synthesized with the presence of nickel catalyst by chemical vapor reaction using a mixture of milled Si and SiO2 powders and CH4 as the raw materials in a graphite reaction cell at relatively low temperature. Their microstructures were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersed X-ray (EDX) and X-ray diffraction (XRD). The synthesized β-SiC/SiOx coaxial nanocables possess a β-SiC crystal core with a uniform diameter of 10–60 nm and an amorphous silicon oxide wrapping layer with tens of nanometers in thickness, and their lengths are up to several tens of micrometers. The vapor–liquid–solid (VLS) mechanism was proposed to elucidate the growth process of β-SiC/SiOx coaxial nanocables.