Catalyst-assisted synthesis of core-shell SiC/SiO2 nanowires via a simple method

Large scale core-shell SiC/SiO2 nanowires with the lengths ranging from several tens to several hundreds of micrometers have been successfully synthesized by using silicon and carbon black as raw materials with a catalyst-assisted chemical vapor reaction process. The nanowires with diameters in the range of 40-120 nm consist of β-SiC core coated with a thickness of 2-3 nm amorphous SiO2 shell and the catalyst played an important role in the growth of the nanowires. The main component of the crucible, namely alumina may be as a novel effective mediator playing an important role in the content of SiO2 during the growth of the core-shell nanowires, which provides a promising method to fabricate nanowires in a large scale production, and an alumina-assisted vapor-liquid-solid (VLS) mechanism was proposed for the growth mode of the core-shell SiC/SiO2 nanowires.