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

Large quantities of beta-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 beta-SiC/SiOx, coaxial nanocables possess a beta-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 beta-SiC/SiOx coaxial nanocables. (C) 2007 Elsevier B.V. All rights reserved.