Synthesis of “A β-SiC nanorod within a SiO 2 nanorod” one dimensional composite nanostructures

Abstract

“A β-SiC nanorod within a SiO 2 nanorod” one dimensional composite nanostructures were synthesized by the combination of a low temperature (1650°C) carbothermal reduction and a high temperature (1800°C) heating of sol-gel derived silica xerogels containing carbon nanoparticles. The composite nanostructures are more than 20 μm in length. The diameters of the center thinner β-SiC nanorods are typically in the range 10–30 nm, while the outside diameters of the corresponding thicker amorphous SiO 2 nanorods are between 20 and 70 nm. Large quantities of SiC rod nuclei and the nanometer-sized nucleus sites on carbon nanoparticles are both favor-able to the formation of much thinner β-SiC nanorods. The formation of the outer coaxial thicker amorphous SiO 2 nanorods is from the combination reaction of decomposed SiO vapor and O 2 during cooling.