3C-SiC nanowires and micro-scaled polyhedra: Synthesis, characterization and properties

Cubic phase silicon carbide (3C-SiC) nanowires (labeled as “Sample 1”) with diameters ranging from 10 nm to 80 nm and lengths up to several micrometers were obtained by using CHI3, Si powder, and metallic Na as reactants at 230 °C. In addition, SiC polyhedra (labeled as “Sample 2”) with smooth surfaces and diameters of 2–5 μm were obtained by using the different amounts of the same reactants at 500 °C. The room-temperature photoluminescence (PL) spectra of Sample 1 and Sample 2 show strong ultraviolet emission peaks centered at 360 nm and 354 nm, respectively. Thermal gravimetric analysis (TGA) curves reveal that the thermal stability (against air oxidation) of Sample 2 is better than Sample 1. The possible formation mechanisms of the products with distinct dimensions were briefly discussed.