Synthesis of SiC@SiO2 Nanocables via a Catalyst-free Carbothermal Reduction Method

Abstract

SiC@SiO2 nanocables (NC), as a new functional nanocomposite, have captured widespread attention due to their excellent performances and widely application prospects. Therefore, it is significant to develop a kind of effective, economical and environmental method to prepare SiC@SiO2 NC. Herein, a catalyst free carbothermal reduction method was developed to synthesize SiC@SiO2 NC fast and efficently, through heating the mixture of silicon powder and silica sol at 1500 ℃ in Ar. The NC is composed of single-crystal β-SiC core and amorphous SiO2 sheath, with the length of hundreds of micrometers and the diameter of 60-80 nm. And the size of the core-shell can be adjusted by the holding time. The formation of the NC is explained based on the experimental data and the vapor-solid (VS) mechanism. The experiment results can also enrich the mechanism, and offer inspiration for their industrial-scale production.