A facile approach to synthesize single-crystalline rutile TiO2 one-dimensional nanostructures

TiO2 one-dimensional (1D) nanostructures such as nanowires and nanoribbons were synthesized by direct heating of Ni-coated TiO powders in argon at 850-920 degrees C and similar to 760 Torr in a tube furnace. The nanostructures were characterized by scanning electron microscopy, transmission electron microscopy, energy-dispersive x-ray spectroscopy and Raman spectroscopy. The 1D nanostructures were found to be single-crystalline rutile TiO2. The preferred growth direction is along the [ 110] direction. The nanowires are roughly similar to 10-50 nm in diameter, and 5-20 mu m in length. The nanoribbons are 0.4-2 mu m in width and 5-20 mu m in length. The growth of nanostructures under different conditions of substrate, catalytic material, reaction gas environment and chemical composition of solid TixOy precursor was studied. The possible growth mechanisms are discussed.