Key Words:characterization; nanostructure; nanomaterials; semiconducting silicon compounds
Abstract:The beta-SiC/SiO2 core-shell nanowires have been synthesized with the presence of iron catalyst by chemical vapor reaction using a mixture of milled Si and SiO2 powders and C3H6 as the raw materials in a graphite reaction cell at lower temperature. The as-prepared nanomaterials are characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, high-resolution transmission electron microscopy, and infrared spectroscopy. The results show that the nanowires consist of a 30-50 nm diameter single-crystalline beta-SiC core wrapped with a uniform layer of about 10 nm thick amorphous SiO2, and their lengths are up to several tens of micrometers. The nanowire axes lie along the [(1) over bar 1 1] direction and possess a high density of planar defects. Some unique properties are found in the Raman scattering from beta-SiC/SiO2 core-shell nanowires, which are different from previous observations of SiC materials. The vapor-liquid-solid (VLS) mechanism was proposed to elucidate the growth process. (C) 2007 Elsevier B.V. All rights reserved.
Volume:308
Issue:2
Translation or Not:no