Wo(3)/TiO2 nanocomposites: Salt-ultrasonic assisted hydrothermal synthesis and enhanced photocatalytic activity

• Key Words:WO3/TiO2 nanocomposites; Hydrothermal synthesis; Photocatalytic activity; RhB
• Abstract:A series of WO3/TiO2 composite photocatalysts were fabricated via a facile salt-ultrasonic assisted hydrothermal process. The obtained samples were characterized by X-ray diffraction, scanning eletron microscopy, energy dispersive X-ray spectroscopy and UV-vis diffused reflectance spectroscopy. It was confirmed that anatase TiO2 and monoclinic WO3 coexisted in the composites. The photocatalytic activity of as-prepared WO3/TiO2 composites for degradation of Rhodamin B (RhB) under visible light irradiation was investigated. The results showed that WO3/TiO2 composites have a higher photocatalytic activity than those of pure TiO2 and pure WO3. First-principle calculations based on density functional theory were performed to explore the electronic structure and illustrate the photocatalytic mechanism of WO3/TiO2. The calculated energy gap was 2.53 eV, which was close to the experimental observation (2.58 eV). Due to the combination of WO3/TiO2, the photoinduced electrons and holes transfer between the WO3 and TiO2 in opposite directions, thus providing sufficient charge separation, which contributed to the photocatalytic activity enhancement. (C) 2013 Elsevier Ltd. All rights reserved.
• Volume:16
• Issue:6
• Translation or Not:no