Silicon oxynitride nanowires derived from polymeric precursors and the optical properties

Amorphous silicon oxynitride (Si₂N₂O) nanowires were prepared by hydrolysis and ammonolysis of SiCl₄ with the present of Ni catalyst in a stream of NH₃at the temperature up to 1300 °C. The products were characterized by X-ray diffraction ( XRD), thermogravimetry and differential scanning calorimetry (TG-DSC) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and selected-area electron diffraction (SAED). The results show that the nanowires are amorphous structures with diameters in the range of 100 to 150 nm. The photoluminescence (PL) spectrum of the silicon oxynitride nanowires shows a strong green light emission peaked at 563 nm and a weak ultraviolet light emission at 289 nm under 220 nm excitation wavelength. The growth mechanism of the nanowires was proposed to vapor-liquid-solid (VLS) process.