A simple catalyst-free route for large-scale synthesis of SiC nanowires

A large number of SiC nanowires were fabricated by a simple catalyst-free method using silicon powders and expandable graphite as raw materials. Digital camera, X-ray diffractometer, Fourier transform infrared spectrometer, field-emission scanning electron microscopy and transmission electron microscopy demonstrate that a large number of loose products were obtained in graphite crucible. The products are composed of single crystalline 3C-SiC nanowires with lengths up to several tens of micrometers and diameters of 20-60 nm. The vapor-solid mechanism was proposed to interpret the growth procedure of SiC nanowires. The expandable graphite as carbon source can provide enough growth space for nanowires, which is helpful to improve the yield of SiC nanowires. The simple method provides a promising candidate for industrial fabrication of SiC nanowires.