Synthesis, Characterization and Photocatalytic Activity of Bismuth Doped Titanium Dioxide under Different Light Sources

Abstract

Photocatalysis is a recognized approach where light energy is employed to excite the semiconductor material and produce electron-hole pairs. These electron-hole pairs eventually involves in the detoxification of pollutants (in air or water) & water splitting. TiO2 photocatalyst shows poor activity in visible light due to its wide band gap (3.2 eV), which restricts its use under Sun light. In the present work, photocatalytic activity of TiO2 was enhanced by doping it with bismuth metal. Pure TiO2 and bismuth doped TiO2 photocatalysts were synthesized in laboratory by using sol-gel method. The characterization of samples was performed using XRD, SEM and EDS techniques. Photocatalytic activities of the samples were determined by the degradation of Rhodamine B dye. The degradation of Rhodamine B followed a pseudo first order kinetic model according to the Langmuir-Hinshelwood isotherm. The primary objective of this work was to decrease the band gap energy of TiO2 by doping with Bi metal.

Keywords: TiO2, photocatalysis, degradation, bismuth: Bi3+, rhodamine BAcronyms: XRD X-ray diffraction; SEM Scanning electron microscopy; EDS Energy dispersive X-ray spectroscopy; TiO2 Titanium dioxide