Preparation of visible-light active N-doped nano-TiO₂ photocatalyst by hydrothermal method

The nitrogen doping nano-titania (TiO₂) photocatalyst was synthesized through a hydrothermal method. Ethylene Diamine Tetraacetic Acid (EDTA) was selected as the nitrogen resource to combine with titanium sulfate (Ti(SO₄)₂) via chemical complexation. The crystal size and phase, morphology, chemical state and photocatalytic ability were analyzed and characterized by X-ray diffraction (XRD), UV-visible spectrophotometer(UV-Vis), field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS). A strong absorption in visible light region was observed. The results showed that the nitrogen was doped effectively and the chemical state of the nitrogen was Ti-N-O and Ti-O-N. Furthermore, the nitrogen doping TiO₂ was expressed as TiO_1.9697N_0.0303 by calculating the concentration of nitrogen. The photocatalytic ability in visible light region could be improved by nitrogen doping in comparison with commercial P25 through the photodegradaton of organic pollutant methylene blue (MB), demonstrating its promising potential in environmental application.