Synthesis and characterization of B-N co-doped mesoporous TiO2 with enhanced photocatalytic activity

Boron doped, nitrogen doped, and boron-nitrogen co-doped mesoporous TiO2 photocatalysts were successfully synthesized via a fast sol-gel method. The prepared photocatalysts were characterized by X-ray diffraction (XRD), thermalgravimetric analysis (TGA), UV-vis diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM), N-2 adsorption-desorption, and X-ray photoelectron spectroscopy (XPS). It was found that the photocatalysts have a typical mesostructure and a large specific surface area. Compared with that of the undoped TiO2, the absorption band edges of the doped samples exhibit an evident red-shift and the absorption intensity of the visible region increases obviously. The XPS analysis shows that Ti-N-B-O structures formed on the surface of the boron-nitrogen codoped TiO2, indicating a synergistic effect of the two dopants that enhances the photocatalytic activity. This was evaluated by the degradation of methyl blue (MB), weak acid red (WAR), and rhodamine B (RB) dyes under visible and UV light irradiation.