Preparation, characterization and photocatalytic activity of N-doped NaTaO3 nanocubes

The N-doped NaTaO3 catalysts with cubic morphology had been successfully synthesized by one-step hydrothermal method, using Ta2O5 and NH3·H2O as the raw materials for the first time. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectra. The results showed that the synthesis parameters such as reaction temperature and reaction time played important roles in the formation of N-doped NaTaO3 nanocubes. As observed by SEM images, when the reaction time reached 12 h, most of the products exhibited the square morphology with the size of 200–500 nm, which can be easily removed by filtration after photocatalytic reaction. The photocatalytic activity of N-doped NaTaO3 was tested by Methylene Blue degradation process under ultraviolet and visible light irradiation, respectively. The results showed that both under the ultraviolet and visible light irradiation, N-doped NaTaO3 displayed much higher photocatalytic activity than that of pure NaTaO3. In addition, NaTaO3-xNx composites exhibited excellent stability in the visible-light photocatalytic process.