Large scale SiC∕SiOx nanocables: Synthesis, photoluminescence, and field emission properties

Large scale, high yield SiC∕SiOx nanocables have been synthesized by thermal evaporation of carbon powders and silicon powders in the presence of Fe3O4 nanoparticle catalysts. Transmission electron microscopy and high-resolution transmission electron microscopy show that the nanocables consist of a 50–300nm single-crystalline β-SiC core wrapped with a 10–20nm amorphous SiOx shell. The nanocables have two broad photoluminescence peaks located around 390 and 460nm when the 250nm ultraviolet fluorescent light excitation is applied at room temperature. The results of field emission measurement of SiC∕SiOx nanocables indicate the low turn-on and threshold electric fields of 3.2 and 5.3V∕μm at the vacuum gap of 200μm, respectively. When the vacuum gap was increased to 1000μm, the turn-on and threshold electric fields were decreased to 1.1 and 2.3V∕μm, respectively. The SiC∕SiOx nanocables with good photoluminescence and field emission properties are promising candidates for ultraviolet-blue emitting devices, flat panel displays, and semiconductor field emitters.