Characterization of silicon oxide nanowires directly grown from NiO/Si

Abstract

Amorphous silicon oxide nanowires (a-SiONW's) were synthesized on a NiO-catalyzed silicon substrate through a simple thermal annealing at 1000-1100degreesC without any additional silicon source materials. The synthesized nanowires were highly pure (no metal catalyst contamination) and very long (hundreds of micrometers). Most nanowires had a diameter in the range of 50100 nm. The nickel oxide nanoparticles play a peculiar role in the synthesis of a-SiONW's. The growth of a-SiONW's is most likely controlled by the solid-liquid-solid (SLS) mechanism. IR absorption characteristics clearly showed bending (796 cm(-1)) and asymmetric stretching (1075 cm(-1)) modes of Si-O-Si bonds in a-SiONW's. An extraordinary UV emission at 370 nm was observed from a-SiONW's, which could be attributed to defect centers of oxygen excess in the nanowires.