Fabrication and annealing behavior of TiO2 nanowires

초록

TiO2 nanowires [1] are known to be very difficult to synthesize. We successfully synthesized them using a hydrothermal method. The scanning electron microscopy image of the nanostructures showed that the diameters of the nanowires ranged from 15 to 30 nm and their lengths a few micrometers. Transmission microscopy and X-ray diffraction revealed that the nanowires were body-centered tetragonal-structured anantase TiO2 single crystal. Photoluminescence (PL) measurement showed that the TiO2 nanowires had an emission band centered at approximately 488 nm in the blue region [2]. The PL emission was enhanced in intensity by annealing in an oxidation atmosphere whereas somewhat decreased in intensity by annealing in a reduction atmosphere. In addition, the mechanism of the enhancement of the PL property of the nanowires is discussed.