Photocatalytic degradation of an azo dye using N-doped NaTaO3 synthesized by one-step hydrothermal process

N-doped NaTaO3 compounds (NaTaO3−xNx) with nano-cubic morphology were successfully synthesized by one-step hydrothermal method and Methyl Orange (MO) was used as a model dye to evaluate their photocatalytic efficiency under visible-light irradiation. The as-prepared NaTaO3−xNx samples were characterized by various techniques, such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectra and GC-MS. The results indicate that NaTaO3−xNx displays a pure perovskite structure when the synthesis temperature is higher than 180 °C. Moreover, as observed by SEM images, the particles of resultant NaTaO3−xNx show cubic morphology with the edge length of 200–500 nm, which can be easily removed by filtration after photocatalytic reaction. Doping of N increases the photocatalytic activity of NaTaO3, and NaTaO2.953N0.047 shows the highest visible-light photocatalytic activity for the degradation of MO. Based on the experiment results, a possible mechanism of the photocatalysis over NaTaO3−xNx and the photodegradation pathway of MO were proposed.

Research highlights
► N-doped NaTaO3 was firstly synthesized by one-step hydrothermal method.
► A possible mechanism of the photocatalysis over NaTaO3−xNx was proposed.
► N-doped NaTaO3 has good stability in the visible-light photocatalytic process.