Defects and growing mechanisms of α-Fe2O3 nanowires

The nanowires of hematite (alpha-Fe2O3) have been characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, energy-dispersive X-ray spectroscopy and electron energy-loss spectroscopy. It is discovered that there are three main shapes of alpha-Fe2O3 nanowires, needle-tip, large-tip, and bamboo-like. A diffusion equation is used to simulate the process of the growth of hematite nanowires. It is found that growing mechanism is quite different from normal vaporliquid-solid and vapor-solid ways, but roughly a diffusion mechanism. (c) 2006 Elsevier B.V. All rights reserved.