Synthesis and Characterization of N-Modified TiO2 for Efficient Removal of Rhodamine B Dye under Natural Sun Irradiation

In this work, Nitrogen modified TiO2 nanoparticles were successfully synthesized via fast acid catalyzed sol-gel route with ammonia solution as a primary nitrogen precursor. The effect of amount of nitrogen was investigated by further incorporating secondary nitrogen in prepared sample with urea precursor by adopting wet impregnation approach. Pure TiO2 nanoparticles were also synthesized for comparison. Prepared photo-catalysts were characterized by Fourier-Transform Infrared spectroscopy, X-Ray diffraction and diffuse reflectance spectroscopic analysis. XRD results confirmed the formation of anatase crystalline phase for all prepared samples. Laboratory test experiments on Rhodamine B (RhB) decomposition under artificial visible light (20W White LED) revealed the highest photocatalytic activity of catalyst doubly doped with ammonia solution and urea whereas pure TiO2 showed poor activity under visible light illumination. The effect of operational parameters such as catalyst dose, solution pH and substrate concentration on photocatalytic efficiency was also evaluated to obtain optimal conditions. Photocatalysis of RhB under natural sunlight with doubly-doped photo-catalyst (T5N2) showed remarkable photocatalytic performance of 99.9% after 1 hour illumination.