Lotus-root-like In2O3 nanostructures:: Fabrication, characterization, and photoluminescence properties

Novel lotus-root-like In2O3 nanostructures with a diameter of ca. 300 nm and a length of 1.5-4.0,mu m have been prepared by annealing In(OH)(3) nanostructures with the same morphology derived from a mild solution reaction. The hierarchical nanostructures are composed of several segments aggregated orderly from In2O3 nanorods with the length of 50-90 nm and diameter of 15-40 nm. The as-prepared products were characterized by X-ray powder diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), and X-ray photoelectron spectra (XPS) in detail. Furthermore, the effects of reaction parameters on the formation of nanostructures were also discussed, and the hydrolysis and oriented-aggregation mechanism was proposed. Room-temperature photoluminescence (PL) spectra of the In2O3 nanostructure showed the peculiar visible emission from the blue to orange region, with the strongest peak centered at 468 nm.