Fabrication and growth mechanism of single-crystalline rutile TiO2 nanowires by liquid phase deposition process in a porous alumina template

Abstract

TiO2 nanowire arrays were successfully fabricated by liquid phase deposition method using porous alumina templates. The obtained TiO2 nanowires were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) analysis. Results of electron microscopic observations indicated that the nanowires were smooth, uniform, and a morphology of tetragonal in shape with width of about 80 nm and several micrometers in length. Selected area electron diffraction pattern, Raman, and X-ray diffraction measurements indicated that TiO2 nanowires were high-quality single crystal with a pure rutile structure after heating at 800oC for 10 h. It was also demonstrated that the nanowire constituents grew preferentially along the <001> direction. Furthermore, the formation process and mechanistic study of the TiO2 nanowire arrays were proposed and discussed in detail. The nanowires were clearly produced by the deposition of TiO2 particles on the inner walls of the nanochannels of the alumina template.