The synthesis and growth mechanism of bamboo-like In₂O ₃ nanowires

Bamboo-like In₂O₃ nanowires are successfully synthesized at 850 °C by a simple thermal evaporation method with an Au catalyst. The morphology of In₂O₃ nanowires is controlled by the N₂ flow rate. Three different morphologies-straight, bamboo-like, and bent and tangled-are obtained under N₂ flow rates of 500, 700, and 1000 sccm, respectively. A possible growth mechanism of the bamboo-like In₂O₃ nanowires is proposed. The bamboo-like In₂O₃ nanowires consist of a stem and nodes, which are formed by rapid precipitation and oxidation processes of indium from an In-rich Au-In alloy at the bottom of an Au catalyst during their growth. Low-temperature photoluminescence of the In₂O nanowires shows a sharp blue emission at 440 nm and a broad orange emission centered at 620 nm. The possible origin of the orange emission is discussed.