关键字:Titanium dioxide;Complexation - Electronic structure - Hydrothermal synthesis - Nanocomposites - Photocatalysis - Photocatalysts - Photodegradation - X ray diffraction - X ray spectroscopy;Composite photocatalysts - Degradation of rhodamin b - Energy dispersive X ray spectroscopy - First principle calculations - Photocatalytic activities - RhB - Salt-ultrasonic assisted hydrothermal synthesis - Visible-light irradiation
摘要:A series of WO<inf>3</inf>/TiO<inf>2</inf> 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 TiO<inf>2</inf> and monoclinic WO<inf>3</inf> coexisted in the composites. The photocatalytic activity of as-prepared WO<inf>3</inf>/TiO<inf>2</inf> composites for degradation of Rhodamin B (RhB) under visible light irradiation was investigated. The results showed that WO<inf>3</inf>/TiO<inf>2</inf> composites have a higher photocatalytic activity than those of pure TiO<inf>2</inf> and pure WO <inf>3</inf>. First-principle calculations based on density functional theory were performed to explore the electronic structure and illustrate the photocatalytic mechanism of WO<inf>3</inf>/TiO<inf>2</inf>. The calculated energy gap was 2.53 eV, which was close to the experimental observation (2.58 eV). Due to the combination of WO<inf>3</inf>/TiO<inf>2</inf>, the photoinduced electrons and holes transfer between the WO<inf>3</inf> and TiO<inf>2</inf> in opposite directions, thus providing sufficient charge separation, which contributed to the photocatalytic activity enhancement. © 2013 Elsevier Ltd.
卷号:16
期号:6
是否译文:否