The synthesis and mechanism investigations of morphology controllable 1-D SiC nanostructures via a novel approach

Single crystalline one-dimensional (1-D) beta-SiC nanostructures were synthesized by the CVD (chemical vapor deposition) method using single crystal silicon wafers and detonation soot as the raw materials. The phase, morphology, crystal structure, and defects of the products were characterized by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. Within a 2 h reaction time, the morphology of the SiC nanostructures can be tuned to nanowires, hexagonal columns and nanopyramids by simply altering the reaction temperature from 1250 degrees C, 1300 degrees C to 1350 degrees C, respectively. Based on the VLS mechanism, we propose a model to explain the novel behavior of the temperature-dependent morphology considering the relationships between catalytic droplets and nucleation.