A simple method to synthesize α-Si3N4, β-SiC and SiO2 nanowires by carbothermal route

α-Si3N4 nanowires, β-SiC nanowires and SiO2 amorphous nanowires are synthesized via the direct current arc discharge method with a mixture of silicon, activated carbon and silicon dioxide as the precursor. The α-Si3N4 nanowires, β-SiC nanowires and SiO2 amorphous nanowires are about 50–200 nm in stem diameter and 10–100 μm in length. α-Si3N4 nanowires and β-SiC nanowires consist of a solid single-crystalline core along the [0 0 1] and [1 1 1] directions, respectively, wrapped within an amorphous SiOx layer. The direct current arc plasma-assisted self-catalytic vapor–solid and/or vapor–liquid–solid (VLS) growth processes are proposed as the growth mechanism of the nanowires.