Nb, F-codoped TiO2 hollow spheres with high visible light photocatalytic activity

Abstract

Nb, F-codoped TiO2 hollow spheres (NFTSs) were successfully synthesized via a hydrothermal method with niobium oxide, hydrofluoric acid, and tetrabutyl titanate. The obtained spheres were hollow, with a diameter of about 2 μm, and the sphere wall was made up of nanorods arranged close together. The NFTSs presented anatase phase with more {001} facets exposed, which could be mainly attributed to F ions which were preferentially adsorbed on the {001} facets during the crystal growth process. Ti3+ states in NFTSs were increased due to Nb, F-codoping, resulting in the decrease of the band gap and the red shift of the absorption edge of the NFTSs. The NFTSs exhibited 20.1% higher photocatalytic speed compared to P25 on the degradation of methylene orange.

Effect of manganese doping on optical and magnetic properties of titanium dioxide nanostructures prepared by hydrothermal technique in the presence of thiourea

“…It can be seen that the morphology of a pure TiO 2 nanostructure sample shifts from a nanorod and nanoparticle shape to a flower‐like shape after Mn doping. This change in morphology might be attributed to the lower growth rate along the {001} direction in the Mn‐doped TiO 2 nanostructure, facilitating crystalline growth in both the {100} and the {101} directions with lower surface energy [16, 17]. The EDX analysis of the Mn‐doped TiO 2 nanostructure is indicated in Fig.…”