Control synthesis of rutile TiO2 microspheres, nanoflowers, nanotrees and nanobelts via acid-hydrothermal method and their optical properties

Abstract

Semiconductor rutileTiO2 nanostructures with a diversity of well-defined morphologies, such as microspheres, nanoflowers, nanotrees and nanobelts, are synthesized via an acid-hydrothermal process without any structure-directing agents. Their morphologies, crystal structures and orientation relationship were characterized by X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy. By controlling hydrochloric acid concentration, anisotropic growth of the rutile TiO2 leads to various morphologies. The synthesis mechanism of rich TiO2 nanostructures was also studied. Finally, the relationship between optical properties and the structural complexity of the rutileTiO2 nanocrystals was characterized.