Study of the effect of annealing temperature on structure of TiO₂ nanowires by oxidation annealing

TiO₂ nanowires were synthesized through annealing of catalyst-gold-coated Ti layer deposited on a silicon substrate in an oxidizing furnace at atmospheric pressure. Our synthesized TiO₂ nanowires were found, through X-ray diffraction measurements, to be crystalline rutile TiO₂. Through varying the temperature of the center of the furnace within the range of 850–1050 °C, we found 850 °C to be the optimum temperature for controlling the diameter of the nanowires. The diameters and lengths of the TiO₂ nanowires formed at this temperature were respectively within the ranges of 70–100 and 400–800 nm. Moreover, it was found that the smaller the nanowire diameter was, the higher the growth rate was, which reflects the point that the growth of the wires was controlled by the transport of the source material to the alloy, and then the diffusion through the liquid phase. - Highlights: • Production of TiO₂ nanowires by oxidation annealing • Study of the effect of annealing temperature on structure of nanowires • The study of growth mechanism • Determining the optimal annealing temperature for controlling diameter size