Novel three-dimensional dandelion-like TiO 2 structure with high photocatalytic activity

Abstract

Pure rutile phase crystalline TiO 2 powder with novel 3D dandelion-like structure was synthesized by using a facile hydrothermal method with TiCl 3 as the main starting material. In such a 3D structure, the nanometer-scale construction elements aggregate together and form a micrometer-scale artificial unit. The typical 3D dandelion structure has an average diameter of 1.5–2 μm and is packed radially by nanorods with [001] preference growth direction. Each individual nanorod is hundreds of nanometers in length, and tens of nanometers in diameter. The obtained 3D dandelion-like TiO 2 powder has a high photocatalytic activity, which is equivalent to that of the commercial available P25 titania powder. Mechanisms of the formation of the dandelion-like structure were also discussed. A different oxidation process of Ti(III) to Ti(IV) during hydrothermal was suggested.