Violet blue long-lasting phosphorescence properties of Mg-doped BaZrO3 and its ability to assist photocatalysis

In this study, a novel Mg-doped BaZrO3 material with the perovskite structure was synthesized by solid-state reaction. Intense violet blue long-lasting phosphorescence (LLP) covering a wavelength range of 320-550 nm was observed for BaZrO3:Mg2+ for the first time, and this LLP wavelength range partially overlaps the absorption wavelength range of the commercial photocatalyst TiO2 (P25). This overlap indicates that Mg-doped BaZrO3 may assist the photocatalytic activity of TiO2. BaZrO3:Mg2+/TiO2 composites were synthesized by a sol-gel method, and the subsequent characterization of these composites suggested that TiO2 nanoparticles were successfully coated onto the surface of BaZrO3:Mg2+ bulk particles. The ability of BaZrO3:Mg2+ to assist the photocatalytic activity of TiO2 was evaluated through investigations of the decomposition of methylene blue. The results revealed that the violet blue LLP of BaZrO3:Mg2+ not only supports the photocatalytic activity of TiO2 in the absence of UV light but also significantly increases the photocatalytic activity of per unit mass of TiO2 under UV irradiation. (c) 2013 Elsevier B.V. All rights reserved.