Visible light photocatalytic degradation of organics on nanoparticles of bi-metallic oxides

Various bi-metallic oxides, Bi2WO6, AgVO3, AgTaO3, BiTaO4, Cd2Ta2O7, InTaO4, CoTa2O6, CeTaO4 and EuTaO4, were synthesized by a solution method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis diffuse reflectance spectroscopy, and Fourier transform infrared spectroscopy (FTIR). All the materials were tested for photocatalytic decomposition of VOCs such as aqueous methylene blue and gaseous toluene. Results indicated that tantalum based ternary compounds like Cd2Ta2O7, AgTaO3 and BiTaO4 could decompose gaseous toluene under visible light irradiation at a much faster rate than TiO2. These compounds also demonstrated very stable activity under UV light irradiation in a longer period of time. Tantalum based compounds could also decompose methylene blue under UV–vis light irradiation but they exhibited lower activity than Bi2WO6 and AgVO3.

► Photocatalysts of bi-metallic oxides based on Ta, W and V were synthesized by a solution method. ► Cd2Ta2O7, AgTaO3 and BiTaO4 can degrade toluene at high rate than TiO2 at visible light. ► Bi2WO6 and AgVO3 exhibit high degradation of methylene blue in aqueous solution at UV–vis light.