Abstract
SiC/SiO2 heterostructures were synthesized with catalytic Mn-Si alloy particles via a simple thermal evaporation process. The inner SiC nanowires were crystalline and possessed cubic structures with a large number of structural defects. Outer amorphous similar to 15 nm thick layers Of SiO2 were 40- 100 nm in diameter. A novel peapod-like silica tubular structure encapsulating Mn-Si alloy particles was also discovered. Magnetic measurements revealed that the Mn-Si catalyzed SiC/SiO2 nanocable heterostructures exhibited tip-end-induced room temperature ferromagnetism. It is believed that the Mn atoms not only played the role of catalyst, but were also responsible for the existing ferromagnetism at the heterostructure Mn-Si-alloy tip-ends. We envisage that the present novel structures, as well as their interesting magnetic properties, should find applications in a future nanodevice design.