Synthesis and photoluminescence property of silicon carbon nanowires synthesized by the thermal evaporation method

摘要

The purity of beta-SiC nanowires is raised obviously by using an ordered nanoporous anodic aluminum oxide template by the thermal evaporation method without any metal catalyst. The microstructures were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and high-resolution transmission electron microscopy. The results show that the synthesized products mainly consist of nanowires, which are single-crystalline beta-SiC with diameters of about 50 nm and tens of micrometers long. The nanowires axes lie along the < 111 > direction and possess a high density of planar defects. The beta-SiC nanowires exhibit the strong photoluminescence peaks at wavelength 400 nm, which is significantly shifted to the blue compared with the reported luminescence results of SiC materials. The blueshift may be ascribed to morphology, quantum size confinement effects of the nanomaterials and abundant structure defects that existed in the nanowires. Finally, the growth mechanism of SiC nanowires and the effect of anodic aluminum oxide template are also analyzed and discussed.