Synthesis and photocatalytic activity of N-doped NaTaO 3 compounds calcined at low temperature

Abstract

N-doped NaTaO 3 compounds (NaTaO 3− x N x ) were successfully synthesized using NaTaO 3 prepared at low calcination temperature as starting material and melamine (C 3H 6N 6) as nitrogen source. The as-prepared NaTaO 3− x N x samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectra. The XRD results indicate that the crystallization temperature of NaTaO 3 is up to 700 °C and the doping of N does not lead to significant structural changes. Moreover, as observed by SEM images, the particle sizes of resultant NaTaO 3− x N x are in the range of 100–150 nm, which are much smaller than NaTaO 3 particles synthesized by traditional solid state reaction method. The photocatalytic activities of NaTaO 3− x N x were examined by methylene blue (MB) aqueous solution under UV light. It is found that the photocatalytic activity of NaTaO 3− x N x depend strongly on the doping content of N, and sample NaTaO 2.961N 0.039 shows the highest photocatalytic activity for the degradation of MB. Furthermore, it is also found that NaTaO 3− x N x catalysts display super structural stabilities during photocatalytic degradation, and could recover their photocatalytic activity after calcination at 500 °C, suggesting a promising utilization of such photocatalyst.