Synthesis of visible light active doped TiO₂ for the degradation of organic pollutants—methylene blue and glyphosate

Background: A simple hydrothermal process was applied to synthesize the doped TiO₂ particles with different concentrations as well as different metal ions (Mn, Ce and La). Methods: The synthesis of Mn-doped-TiO₂ nanoparticles was done by using a hydrothermal method from hydrolysis of titanium tetrachloride in aqueous solution. The photocatalytic activities were checked by studying the degradation of two model organic pollutants. Results: The material was characterized by X-ray diffraction, scanning electron microscopy, and UV–Visible spectroscopy. The X-ray diffraction pattern studied for doped TiO₂ particles suggests the anatase phase with a crystalline nature. Doped TiO₂ particles showed a porous and complex nature with a highly rough surface. The photocatalytic activity of Mn- Ce- and La-doped TiO₂ with different metal-ion concentrations of 0.15-0.60% show that the degradation rate of all of the pollutants increases with an increase in the dopant concentration from 0.15 to 0.45%, and a further increase in the dopant concentration decreased the degradation rate. Conclusions: The results indicate that TiO2 with a concentration of 0.45% for all metal ions (Mn, Ce and La) shows the highest activity. Among studied dopent TiO2 with Mn (0.45%) showed the best degradation activity.