A new rapid reduction-carbonization route to nanocrystalline beta-SiC

Nanocrystalline beta-SiC was successfully synthesized at 600 degrees C thro ugh a new rapid reduction-carbonization route, in which metallic Na was use d as the reductant, and activated carbon and tetrachlorosilane (SiCl4) were used as source materials. X-ray powder diffraction indicates that beta-SiC with high crystallinity is obtained. Transmission electron microscopy imag es show that the as-prepared SiC powders consist of spherical particles wit h an average diameter of 25 nm. An atomic ratio of Si to C of 1.08:1.00 was determined from X-ray photoelectron spectra. A possible formation mechanis m for nanocrystalline beta-SiC is proposed.