Preparation, characterization and photo-catalytic behavior of WO3-TiO2 catalysts with oxygen vacancies

TiO2 photocatalysts compounded with WO3 were prepared via a modified hydrolysis process and the 2% WO3-TiO2 catalysts with different oxygen vacancies were obtained by calcination at 873 K in H2 atmosphere. The catalysts were identified using X-ray diffractometry (XRD), specific surface measurement (BET), electron paramagnetic resonance spectroscopy (EPR), UV-Vis diffusion refraction spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of 2% WO3-TiO2 with different oxygen vacancies was investigated employing splitting of water for O2 evolution. The results indicate that appropriate oxygen vacancies can obviously improve the photocatalytic activity of 2% WO3-TiO2 catalysts, and using Fe3+ as an electron acceptor under UV irradiation in 12 h, the maximum rate for O2 evolution is 667 µmol/(L·h).