One-step synthesis of rutile nano-TiO2 with exposed {111} facets for high photocatalytic activity

In this work, we demonstrate a novel synthesis of rutile nano-TiO2 with exposed highly active {111} facets. This TiO2 was obtained by a simple one-step hydrothermal route with the assistance of NaF and HCl. In this progress, the Cl- causes the formation of rutile phase while the F-controls the exposure of {111} facets. With a best mole ratio of Cl- and F-, the percentage of exposed {111} facets in such rutile nano-TiO2 can reach 96%. This rutile nano-TiO2 with exposed {111} facets has larger specific surface area and as much as 3 times higher photocatalytic activity than rutile TiO2 nanorods with exposed {110} facets. This results confirm the {111} facets have higher photocatalytic activity than {110} facets. In a deeper analysis, more surface unsaturated O-2c modes on the {111} facets cause higher adsorption and degradation ability which enhances the photocatalytic activity. The present work shows a further prospect of hydrothermal synthesis for controlling preparation of nano-materials.(C) 2015 Elsevier B.V. All rights reserved.